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tradmanclimbs
Ice climber
Pomfert VT
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Mar 12, 2008 - 03:25pm PT
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Ever climb at Deer Leap in killington? www.deersleapvt.com
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cleo
Social climber
Berkeley, CA
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Mar 12, 2008 - 03:31pm PT
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yup! once or twice. i wasn't much of a climber when i was living in vermont. come to think of it, i'm not much of a climber now!
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healyje
Trad climber
Portland, Oregon
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Mar 12, 2008 - 03:59pm PT
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Being driven down does relieve some force - until you are against the anchor rope and then the hip belay starts acting more like a scissors guillotine and sort of feels like you are being cut in half in a demon magic act.
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tradmanclimbs
Ice climber
Pomfert VT
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Mar 13, 2008 - 06:17pm PT
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Here I am desperatly trying to chop away the outer layer of slush to find some decent ice for a screw on the 4th pitch of The Last Gentleman. I realized that the reason I can't properly calculate the fall factor is because I have no head! ;)
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dirtineye
Trad climber
the south
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Mar 13, 2008 - 09:04pm PT
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Just a bump to get past all the idiot threads, and to propose that maybe there ought to be a thread about how most posters don;t know when to stop beating a dead horse, as in, nobody ever said you should calculate ff while climbing, rather, that you should have some idea of what FF means so that you won't climb yourself into big trouble with out having some idea of what might happen.
Nobody else seems to care that it's tied up with impact force felt by the faller and what that means.
Oh well.
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Willoughby
Social climber
Truckee, CA
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Mar 13, 2008 - 09:15pm PT
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Chuck Norris could survive a Factor 3 fall, but he never falls...
Wait, wrong thread?
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Karl Baba
Trad climber
Yosemite, Ca
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Mar 13, 2008 - 11:22pm PT
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TIG wrote
"I will give you the short answer.
If you don't fall, you won't die from falling."
I'll give you the better answer, you don't get screwed up from falling, you get screwed up from HITTING!
That's why a 100 foot factor 1.2 fall is WAY more dangerous than a 10 foot factor 1.2 fall.
Clean fall? In trad climbing, a clean long fall is pretty rare.
Peace
Karl
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dirtineye
Trad climber
the south
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Mar 14, 2008 - 03:26pm PT
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But to do that Karl you'd have to run it out 50 feet past your last pro. Maybe that's not the best idea, which was sort of the point of this kind of thread.
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AE
climber
Boulder, CO
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Mar 14, 2008 - 10:35pm PT
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Two divergent schools of thought; tradmanclimbs seems to reveal the greatest scorn for the "overthinkers"; too bad, for their ilk is the reason you have nylon instead of hemp, bolts and cams and screws that all actually hold falls, etc. etc.
Craig Luebben set up a "real fall" test at the BRC last year, with dynamometers on the falling weight and belayer and top piece, and it revealed many surprises, regarding how and where fall forces are dissipated, as well as myths retold endlessly about the "dynamic belay."
A brief summary of revelations:
The greatest forces are never on either the belayer, device, nor leader but always on the top piece that holds the fall.
The force that MUST be dissipated is only related to the weight of leader, and TOTAL distance fallen.
Falls can be caught by belayers anchored to the floor; in these setups the device, even a "dynamic" one, is still usually actually locking off, and the fall energy is absorbed by the rope stretching, sliding, and heating up the top carabiner; although the gym setup could not generate extreme falls, if such high force is ever generated, it will max out at the rope's rated "impact force"; the number of seconds this load is maintained determines how the total fall force is absorbed.
In the safer and simpler world of sport falls, and especially indoors, it IS TRUE that jumping up to catch a fall DOES significantly lower the final impact on the top piece; ALL the force generated is absorbed by friction of the rope over the top 'biner, and the belayer is just a counterweight. If you substituted a pulley at the top, both parties would continue up (belayer) and down (leader) indefinitely.
Such a soft catch seems like a good deal, except when the leader breaks the neck of an innocent bystander, or the belayer, or the belayer jams a hand into the first pro, or has a Gri Gri or Cinch get yanked in to the first biner and is automatically released.
Remember, a longer fall might feel softer, but the total force will be greater, and it all has to go somewhere.
These too are all real-world test results, not just theory.
Some of the simpler ways to think about fall factor without getting uber-tech:
-Rope stretch is the final arbiter; that's why leading on static rope is deadly, and why a short shock-load on an anchor (via too static daisys, or a piece of cable clipped to a hammer) can break
harnesses and help remove stuck pitons and bolts.
-Falling 3 feet on 3 feet of rope is, from the rope and anchor's point of view, the same as falling 100 feet on 100 feet of rope.
The only difference is that other problems may affect the falling climber, ie hitting something from 100 feet is obviously worse than from 3.
Subtle but undeniable facts of physics support real-world experiences like, if you fall 5 feet or 50 out straight sideways from your last (bomber) piece, and you fall free to pendulum, the top piece and you will feel no more than 4 times your weight, in either case. BUT, if you traverse straight away from a corner that contains the last piece, and you fall into the corner instead of penduluming, you will hit the corner wall with the same full force you would hit the ground with, from the same distance - a clear example of where fall factors alone aren't the whole story, as 5 feet is gonna feel a lot different than 50!
Petzl used to make a compelling demo at their testing pit, where you got to stand and belay a real person; given any device of your choice, you then feed out a mere 3 feet of slack, then the "leader" simply steps off the ledge.
a) with 2 exceptions, NO belayer using any type of belay device
can catch this leader, still way less than a full factor 2 fall- they drop into the pile of foam pads below, safe but humbled.
Once a belay device allows slippage, the slip accelerates, and as someone else correctly observed, human hands alone cannot stop the fall.
b) the 2 exceptions (now likely more w/ the Cinch, and a few other full-autolocking devices available) were the Gri Gri, and the Munter Hitch (!).
This reveals the classic shortcomings of using "intuition" alone to make life-or-death decisions on climbs. It seems so trivial, to just head out from the anchor without clipping in to even a single 'biner at the anchor, first.
Tom Dunwoodie, computer genius as I recall, Devil's Lake guide co-author, solid trad 5.11+ leader, died on the DNB several years ago, when he and his partner fell 1500 feet or more. The gear attached to them suggested that one or more cams were the belay anchor, but then no more intermediate pieces suggested any pro between belayer and leader. When one fell, the other not only could not hold, but apparently the shock impact likely popped the belay anchors. "Bomber" anchors aren't always that bomber, and especially cams versus old school hexes and passive gear that could be visually checked in many cases.
You don't have to do the math in order to climb, but as there are consequences for misunderstanding the where and how of the important forces that will kill you and/or your team, I have to say that we will all have a beer in tradmanclimbs memory when he someday tries to argue or intimidate good ol' gravity.
It, even more reliable than rust, never sleeps.
And, gravity is more than a theory - it's the Law.
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healyje
Trad climber
Portland, Oregon
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Mar 15, 2008 - 12:33am PT
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Yeah but.
I'm with tradman here - never once ever thought of fall factors, ever. What you call 'fall factors' I call situations where, unless you are mentally deficient or insanely reckless, it is apparent, obvious, and 'intuitive' you are going to be hating it in a big way if you f#ckup. I don't - and never have - needed algebra or physics to explain the true nature of such situations in climbing or their potential for untowards consequences.
Enter the world of rescue, industrial or entertainment rigging and you've just entered another universe where things may not always be obvious and intuitive and understanding the mechanical tolerances, safety factors, and limits of systems can be quite helpful to avoid a fatal faux pas. Then again, they did manage to build massive cathedrals throughout Europe without knowing the detailed engineering specifics of the various loads and forces involved. Instead they simply recognized and dealt with them (genius in its own right).
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Ed Hartouni
Trad climber
Livermore, CA
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Mar 15, 2008 - 01:02am PT
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...but AE has a point..
From the 2002 ANAM:
PROTECTION PULLED OUT - FALL ON ROCK
California, Yosemite Valley, Middle Cathedral Rock
On July 12th at 1:00 p.m., a fisherman in Yosemite Valley reported seeing two climbers fall from high on Middle Cathedral Rock. After speaking with this witness, I hiked up to the base of the wall, where I found the bodies of Myra Eldridge of Boulder, CO, and Thomas Dunwiddie (ages unknown) of Denver, CO, just east of the Direct North Buttress route.
No one else witnessed the accident. Its exact cause will never be known, but certain things were clear from the condition of the climbers' equipment at the time they were found.
The team was leading with two 9mm ropes, and both climbers were properly tied to both ropes. Dunwiddie was equipped as leader, with each of his two ropes passing through Eldridge's belay device (an ATC). About 25 feet of each rope separated the two climbers; no lead protection was found on either rope.
Their anchor -- which appears to have pulled in its entirety during the accident -- consisted of the following. One 3/8-inch Alien and one #4 Black Diamond Stopper were clove-hitched together to one of the lead ropes approximately three feet from Eldridge's tie-in point. Two double-stem Camelots, .5 and .75 were each independently clove-hitched about a foot and a half apart on the other lead rope with 15 inches separating the lower piece form Eldridge's tie-in point. There was no evidence that bolts or other fixed protection were involved in the anchor.
All of the anchor pieces were severely damaged, though it is impossible to know whether the damage occurred when they were pulled out or during the fall and final impact. Nevertheless, the two Camelots were each bent in a similar way suggestive of a severe downward force after being placed in a vertical crack.
A loose quick-draw and a few carabiners were also found at the base. Their original purpose could not be determined, and they may have simply unclipped from the falling climbers -- a common occurence.
Analysis
Both Dunwiddie and Eldridge were skilled climbers, and in the days prior to their deaths they had completed a number of challenging free and aid routes in the Valley. Based on the location of the bodies, and on the topo of the Direct North Buttress found in their possession, they were probably on the DNB at the time of their accident. Rated at 5.10c and known for both its length and route finding difficulty, the DNB includes several sections of "run out" climbing and loose rock.
What can we learn? This accident hits close to home for most climbers because the party involved was very experienced with difficult climbing and familiar with Valley rock -- as have been at least a third of Yosemite fatalities, historically. Other factors, such as rock fall from above, may have been involved, but the prime suspects are basic anchor and leading concepts that all of us are often tempted to ignore: avoiding anchors in suspect rock, sharing the load to an adequate degree, and stuffing in that first (and second) lead piece right off the belay. If you can't meet these criteria, continue on with the realization that your survival may depend only on your climbing skill and on the quality of the next handhold. At least five other cases of complete anchor failure (protection pulling out -- not breaking) have occurred in the Park in the last 30 years. (Source: Lincoln Else, Climbing Ranger, Yosemite National Park)
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TradIsGood
Chalkless climber
the Gunks end of the country
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Topic Author's Reply - Mar 15, 2008 - 09:52am PT
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healy and others fall into the common trap of anecdotal evidence (or cherry picking).
Old buildings built without knowledge of engineering are still standing, therefore knowledge of engineering is not useful in building.
It ignores all of the ruins. It ignores things like the Tacoma Narrows bridge disaster.
In its most extreme form, one can prove that smoking does not cause death by lung cancer. How do we know? A survey of 1000 smokers all say that they are still alive.
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happiegrrrl
Trad climber
New York, NY
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Mar 15, 2008 - 10:56am PT
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I don't think anyone in this thread has said that the knowledge of FF is useless. Especially when used in when designing gear.
What I am reading, is that people(myself included) aren't interested in having an ongoing mathematical application running in their head as they climb.
To those of you who are saying one should fully understand and be capable of running a FF calculation at any given moment, I have a question: Do YOU run these calcs - en route? If yes:
 Is it something that is "part" of your climbing experience, in the way another person might often look down to see how the rope is hanging after they sling a piece? I'm talking "On belay? Belay on. Climbing. Climb on." and then the leader "switches on the Fall factor calculator, and runs it the whole way through, as sort of an added dimension to the factors in leading.
Is it something that you stop to consider as you place a piece of gear? Every time? Sometimes?
Is it something that pops into your head at dicey moments?("hmmmmm, what would happen if I do fall, at this moment when I get the feeling I shouldn't?") BTW - Maybe this is akin to the crux of the "faith vs. science" argument of God's existence - hahahah
One more question - On the accident report above, I am reading it that the anchors were placed and connected directly to the rope with no slings. Just the piece, a carabiner, and the rope clove-hitched. Particularly the two cams, with a bit of rope bewteen them, seems to me that it would have added force on the anchor, one piece at a time.
Why wouldn't he have added the slings and attempted some equalization of the pieces? That's rhetorical, actually. What I should say is - Wouldn't it have reduced the force on the anchors to do so? I've never thought of, nor seen anyone, nor read anywhere, of anchoring as was written, and it seems to go against my "intuitive" understanding of shocking the anchor. Even the sling's movement as the fall comes onto the anchor - seems to me it would change the impact whereas a direct clove yards the piece harder(or with less ability for the gear to shift, or brace itself and bite down, I guess) at impact.
(Do I deserve to have my leader stripes ripped from my uniform because I can't calculated the difference of force applied, much less show my work? Or is it "enough" to get a feeling adding slings and attempting equalization between pieces would be a better idea.)
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Ed Hartouni
Trad climber
Livermore, CA
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Mar 15, 2008 - 12:01pm PT
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happie- the method of building an anchor described in the accident report is very common, and most people who have climbed in the Valley would have seen the "old dads" employee this method. The fact that there were two ropes is even better, as there was equalization between the two tie-ins. I will often come to a belay spot, put a bomber piece in, clove-hitch my rope to it and yell "off belay" and setup the rest of the anchor. Saves time on the change over because it frees the second up to start breaking down their anchor. I then proceed to find a couple of good placements, lately I'd put a sliding-X on those two pieces and have my three-point anchor, a sort of hybrid.
I always try to find anchor placements such that any one would hold a severe fall. This is not always possible, and my judgement may be erroneous, especially considering the role the rock plays. If the rock breaks under the force of a load it is the job of the other anchor points to hold. My way of looking for anchors is not to depend on a single rock feature (e.g. putting all your pieces under the same rock flake, or in the same crack). But you don't always get what you want...
Too much can be read into the accident report, and as the report states, the exact cause of the accident will never be known. The reason I posted it here was complex. One was to point out the a factor 2 fall generates a tremendous force, here enough to pull four pieces in the anchor system. The second was that the fall was only 25 feet some of the talk on early posts might be interpreted by inexperienced climbers as "short falls are casual" they are not. Finally, this was an experienced team using well developed skills and applying there expertise on a challenging, but probably not difficult climb for them, which they had climbed previously.
The report strikes "close to home" because anyone climbing with them would have thought that they did everything right. It is the primary reason that we should consider all of this discussion as important, the physics analysis is especially important because it does not depend on personal experience.
The physics analysis is a simple statement of fact regarding the forces involved in falling. The accident analysis is the important legacy these climbers left us illustrating the facts.
The tragedy need not be repeated.
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dirtineye
Trad climber
the south
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Mar 15, 2008 - 12:01pm PT
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Not for the last time obviously, NOBODY has said this.
"To those of you who are saying one should fully understand and be capable of running a FF calculation at any given moment, I have a question: Do YOU run these calcs - en route?"
typical strawman bullshit from yet another misguided fool.
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TradIsGood
Chalkless climber
the Gunks end of the country
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Topic Author's Reply - Mar 15, 2008 - 12:27pm PT
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"Fool" might be a bit harsh.
Some folks here can and are willing to put a lot more thought and analysis into problems than others.
Happie. to her credit, is still asking questions rather than just saying the whole line of thinking is unnecessary.
To be sure, she has not read carefully and has somehow read into the thread that people are recommending the calculation of FF while climbing. But the one useful question she asked was whether FF should be considered in the placement of a piece.
Ed answered that w.r.t. a piece as part of an anchor. On a climb, it may be very important to understand whether a placement will handle a fall. (If you are not placing pieces with that intent, it would be far simpler to solo ropeless, right?) FF will play an important role in determining the load on a placement. As Ed points out, either the piece or the rock could fail. How straight the line is to that point is important. If you are experiencing a lot of rope drag 100 feet out, perhaps that 10 foot fall is going to be a hard FF 1.6 fall instead of a mild 0.1 FF fall. So yes, considering it may often be important, since it just might have 16 times the load under those circumstances. Perhaps that little tiny nut or cam should have a screamer attached. Or perhaps you should consider working in a couple other pieces.
Does anybody run a calculator in his head?... Of course not. But a quick analysis before going on belay at an anchor (or even at the base) might alter your plan for the better. If you fall 4 feet up, how will that load transfer to your belayer? Up, down, sideways? It all depends on the geometry. If you are leading you certainly are responsible for your own safety as well as that of your partner. Are you leaving him with the ability to make a safe catch? If you aren't leading through a power point of some sort, does your belayer even understand that he will have to brake up instead of down?
Quick now. If belayed directly off the harness, and the faller does not hit anything, will this catch be pretty soft?
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happiegrrrl
Trad climber
New York, NY
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Mar 15, 2008 - 12:38pm PT
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I'm going to break my TWO YEARS of ignoring the bleating, whining, nasty posts from dirtineye to reply.
Firstly - My statement is not an attempt at arguing a point. It's simply I question I asked of certain people, particularly TiG. there was no ulterior reason for asking it; I simply wondered about his/their thought process.
If you'd like, feel free to answer the question.
Secondly - f*#k yourself.
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happiegrrrl
Trad climber
New York, NY
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Mar 15, 2008 - 12:57pm PT
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Ed: I will clove hitch into a piece and call off belay too, if I have a good stance that I feel it's a "just in case I do something stupid" piece until I build the rest of the anchor.
I was meaning that, it seemed, he'd done the first piece, and then run the rope right to the second piece, instead of building a 2-piece placement, equalized, and then clipping into that. Anyway - no need to discuss that point further, I guess.
TiG wrote "has somehow read into the thread that people are recommending the calculation of FF while climbing."
It's NOT that I have read people are specifically suggesting that. I was comparing it to the suggestion - which WAS written - of others saying people didn't care a whit about FF, even as used in designing gear. AND - I simply wanted to know just HOW in depth someone, such as yourself, kept the FF in mind WHILE climbing. Was it something you thought about at a placement? Or, was it something that was much, much more prevelent in your thought process while leading?
You never, that I recall, mentioned that and so I was left to wonder. Not really a huge issue....
And: "FF will play an important role in determining the load on a placement....How straight the line is to that point is important. ...So yes, considering it may often be important, since it just might have 16 times the load under those circumstances. Perhaps that little tiny nut or cam should have a screamer attached. Or perhaps you should consider working in a couple other pieces."
For myself - I DO consider what a fall will be(in terms of hitting stuff and how hard the piece will be impacted). BUT - I do not do it with a mathematical equation. I would intuit the situation, and I BELIEVE that is what MANY of the other posters are also saying as well.
I don't know that one needs to be fully cognizant of the calculations to get a pretty good idea on the consequences....
I think that, on both sides of this argument, people are reading the posts of others and making assumptions that fit their perceptions.
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TradIsGood
Chalkless climber
the Gunks end of the country
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Topic Author's Reply - Mar 15, 2008 - 01:02pm PT
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"For myself - I DO consider what a fall will be(in terms of hitting stuff and how hard the piece will be impacted). BUT - I do not do it with a mathematical equation. I would intuit the situation, and I BELIEVE that is what MANY of the other posters are also saying as well.
I don't know that one needs to be fully cognizant of the calculations to get a pretty good idea on the consequences"
It is exactly this intuition that is the problem. You can't intuitively know the answer without understanding what fall factor is, and why it is important.
Ed has made this point with respect to intuition on a number of occasions.
Intuitively, now! Please answer this question.
If you fell from 3 feet above your belayer's device or 5 feet, which fall would be harder, and by about how much? (Belayer is anchored, no power point, you do not hit anything.)
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dirtineye
Trad climber
the south
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Mar 15, 2008 - 01:12pm PT
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HAHAHA , well dear crappiegrrrl,
First of all , kiss my a$$, you stupid, witless, reeking turd in the punchbowl of climbing.
Second. learn to read for comprehension.
Third, try responding to what is actually written instead of what's being shown your demented, twisted, self absorbed personal mental theater.
Maybe if you actually had a clue it would be different, but as I've seen you mishandle threading your belay device twice, and you had no idea you'd done it, I really have to wonder how you can live with your self and all the crap you write, seeking to inflate your image as a climber.
Furthermore, for someone who can't seem to climb past a 5.4 move without fretting for over 20 minutes, you have a lot of nerve lambasting others aboout their climbing, which you tend to do on a regular basis.
You seem to feel it is your right to go off on people over nothing, and yet your skin is thinner than rice paper.
You are disgusting.
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