hafilax: that is YOUR question, not Dingus's. He wrote: "There is virtually no proof whatsoever that limiter knots provide any sort of benefit at all." I'm not getting the word "significantly" from that.
By the way, I agree with the point made above that an advantage of limiter knots is that it will reduce the change in the position of the anchor if a piece pulls, and that may be more of a concern that the change in overall force felt on the anchor when a piece pops. For example, if you're doing what is common which is standing near the edge of a ledge at a belay and think it's just fine to drop down a foot or whatever when a piece pops, feel free to think that and maybe you're right. I find it to be at least a somewhat troubling event--but hay, whatever floats your boat.
On your point that "Even with long slings I don't think limiter knots will make a lick of difference as long as there is a reasonable amount of dynamic rope in the system especially given how much friction there is in a sliding-x when it has to rapidly change position": I'm interested in what you thing a "reasonable amount of dynamic rope is. The foot or two that connects the belayer to the anchor (in, let's say, a hanging belay scenario)? When that foot or two is already being stretched by holding the weight of the belayer? If the sling is a double or triple length"?
I've edited the posts mostly to correct some typos (I know some remain) and also to avoid bumping the thread when I just have another point to make. My goal is to improve the quality of the reading experience and not to continually bump the thread, especially if no one else has posted.
Why do you ask, is this a problem?
Edit--see halifax--here's an example. I saw shoo's post made above, and I don't see a need to make a new post, rather than just edit this one. Shoo--I don't know how "respected" Dingus is a climber, just like neither of us knows anything about each other. Being an rc posting legend is nice, but sorry, that don't mean jack to me when discussing anchors. I just know what he posted on this thread, and that's all I'm responding to.
Finally I got sick of this nonsense and just posted to Luebben's anchor book to settle this once and for all, which has now been done. (And I'm not saying you should always or even usually (or even ever, if you're using relatively short slings) tie limiter knots, which adds to the level or ridiculousness here.)

hafilax, I thought we were getting somewhere, but now I'm concerned about a relapse.

Dingus wrote the following: "There is virtually no proof whatsoever that limiter knots provide any sort of benefit at all."
Putting aside anchor forces, I believe you noted earlier in this thread the advantage of reducing the change in anchor position. Do you now deny that that is proof, whatsover, of "any sort of benefit at all"?

Dingus's absurdity on this thread is not that he doesn't use limiter knots; it is the failure to acknowledge that they have obvious benefits in some cases. If the benefits don't exceed the costs for him and he avoids the cases where knots are really necessary (long slings), I have no problem with that.

It's also telling that neither you nor Dingus want to have anything to do with the discussion of whether you would use a sliding-x on a long sling (let's say a 20' sling) without limiter knots to, say, set up a top rope. Looking at arguments made in the extreme is a valid way to test the quality of the argument in other circumstances (and use of a long sling to set up a TR is really not so extreme--in fact, it happens hundreds of time across the country every weekend). I respectfully submit that the 20' sling does in fact prove that Dingus's potion in this thread has been absurd, and that's what "got my panties."

If for some crazy reason you still want to debate this, I will extend the invitation I made to Dingus to try to develop a test to submit to Aric or another qualified tester, with a little money riding on the result. For some reason Dingus seems to have been grossly offended by that even though he earlier in this thread issued a challenge. I think it may be interesting. If I "lost," that's great, I wouldn't have to waste time with limiter knots (except for the problem of anchor translation, which may in fact be the more serious issue).

I'm not reading that ^

geez us man, paragraphs.

I'll say this briefly, seeing as it's about as close to "correct" as you can get in this kind of conversation, and let you figure out why:

Extension of a given length has a negligible effect on the overall strength of any real world anchor as long as the people/other loads connected to that anchor are connected using a length of dynamic cord that is "long" relative to the amount of extension. This caveat is met in any anchoring situation, basically, which consists of shoulder length slings and a rope tie-in. Yes, you are capable, I'm sure, of coming up with an asinine counterexample. Don't bother.

As to using limiter knots to make the sling more redundant: I am much more sympathetic to this line of thinking, especially on a hanging belay with two people and 6mm slings... but I'd almost always rather just use two slings, both sliding x'ed, and be done with it. Faster, more redundant, less knot tying and untying, etc.

I don't know if I'm correct or not.

But then again, neither do the limiter knot folks.

DMT

Edit edit: I'm reading a fascinating book called Fooled by Randomness by Nassim Taleb (mostly but not exclusively about financial markets).
The author was called upon by some critics to justify his points with empirical evidence. He replied that "logic does not require empirical verification . . . It is a mistake to use . . . statistics without logic, but the reverse does not hold: It is not a mistake to use logic without statistics."
So you all can chew on that if you fault my lack of "proof" that limiter knots are not "pointless."

Also, you completely fail to address the inherent problems caused by the anchor extending, even if that results in minimal loss of strength. Would you like to address my 20' long sling example used to set up a top rope? So far I haven't had any takers.

My internet posting has little to do with "real life," but if I saw some "climbers" using a 20' sling to set up a TR with no limiter knots in real life, that might be a rare time when I would speak up to address some safety issues.

I mentioned this above in the form of another question. It's a sidestep I know.

Anyway to reiterate, does one actually set up a sliding X on 20 ft slings for a toprope? I'm trying to think up a scenario where I would rather the 20 foot sling sliding along the rock to equalize poor anchors instead of just a powerpoint.

I guess someone who doesn't think there is any theoretical problem with using a sliding-x without limiter knots would think it's a fine way to set up a TR, even with a long sling. It equalizes (at least to some extent), and that's a good thing.

How about this example: there are trees near the top of a cliff on which you would like to set a TR. The trees are good--you're pretty damn sure one tree would be fine, but pretty damn sure isn't quite good enough so you use two. How about you girth hitch a sling (or maybe 2--we're being safe here) around each tree, then take take your mega 20' sling (hell, how about a 40'--I'm not a big TR guy, but that's not that uncommon), and connect each girth hitched tree with a big old sliding x that drops nicely below the top of the crag. Use 2 lockers on the sliding-x, (remember, your text-book safe).

Great anchor, no? Yeah you could tie a powerpoint (codelette style), but why not just get the benefit of the sliding-x? That way, you don't have to untie the figure-8 when you're done, which can a little tough if a fat-ass top roper has been hanging all afternoon. (Remember--one reason not to use limiter knots is you don't want to untie them--that should also apply to a cordelette powerpoint knot).

Anyway, Dingus and halifax have piped down on this thread and there are some new posters now, and I don't think you've read all of the above posts. The problems started when Dingus defiantly challenged anyone to "prove" limiter knots could have any advantages, ever. He did it in what I perceived to be an insulting way, and I responded in kind to some extent (and then I admitted I regretted that). I ended the serious discussion (if there ever was one) by a cite to Luebben's anchor book, and that should have been that.

Now some of you seem to be saying that limiter knots aren't necessary when using shoulder length slings--I've got no problem with that. That sure as heck is NOT the position what started the trouble, and so it's really apples and oranges at this point.

True, but a funny one, with the closet hook bolts and the "climbing in the closet" comment.

On a side note, who does a sliding X on 20 foot slings?

Do let me know if you come up with one shred of PROOF that limiter knots provide benefit.

Retro Thanks
DMT

Is a direct, on-point quite from a published book on climbing anchors PROOF, in your view? If so, I will get you said quote. If not, I won't waste my time.

Majid, is that you?