Intuitively, I do buy into the belief that some equalization of multiple pros is better than loading each one sequencially.

Jim, please, do write that article.

In the swing resulting from an off-centre loading, some of the equalization systems make the tape or cord run through several of the biners or rings involved (Alpine equalizer, ACR, upper right part of Neoshade's latter system, etc.) whereas for others, it runs only through the central biner (eg the two-arm equalette with extension-limiting knots). I can feel that the former have more friction than the latter. On the other hand, in an off-centre loading situation, the pro closest to the direction of pull is initially going to get a greater portion of the load. So, without a more detailed description of the test, I keep wondering if the large difference you are reporting is really due solely to biner friction or if it might be due to a combination of friction and skewed loading.

Although this discussion has put a big question mark for me over the equalizing set-ups that involve friction over multiple biners, for now, I remain convinced that, even with less-than-perfect distribution of the load and the need to pick a compromise between the range of equalization and the limitation of extension, low-friction equalizing belays are still preferable to the alternatives that don't equalize at all under an off-centre load. Intuitively, I do buy into the belief that some equalization of multiple pros is better than loading each one sequencially.

The angles aren´t relevant, in practice you don´t have the option to change them anyway and the effect is what matters not the cause.
However since I´m working on the cause as well I did the easy thing to check and eliminated the angles altogether by arranging the points vertically above each other. You get the same results except that the narrower the angle between the pieces makes the sensitivity of the load direction more and more sensitive until the vertical case where the difference between the high and low on the pieces is physically impossible to detect and it is going to be impossible to manually equalise as well.

The big question is are there alternatives which give better results than equalising systems which often give results worse than just guessing. As the DAV decided the benefits of minimising extension are clear whereas the benefits of dynamic equalisation are effectively non-existent so redundancy is the choice giving clear benefits.

Jim

I've been climbing for 45 years and have never used a 'lette of any type. Why complicate things? I'm with patto on this one. Use the rope and the PAS which you'll have already girth-hitched on your harness if you're smart.

Ed, if you're not swapping leads, what do you do? Just untie and swap rope ends?

My pleasure Sir.

I´ve just been trying some tests with average punters to see how well they achieve equalisation and one of the most popular `equalising´methods got a load distribution of 85%, 15% and 0% and with no apparent way of pre-determining which was going to be which.

We were impressed!

Jim

I´m writing a bigger article but I´ve been touring around in a tent with my family for the last 3 weeks so not a lot of internet or writing time. Got back home a couple of hours ago so I´ll press on a bit!

Jim

The angles aren´t relevant, in practice you don´t have the option to change them anyway and the effect is what matters not the cause.
However since I´m working on the cause as well I did the easy thing to check and eliminated the angles altogether by arranging the points vertically above each other. You get the same results except that the narrower the angle between the pieces makes the sensitivity of the load direction more and more sensitive until the vertical case where the difference between the high and low on the pieces is physically impossible to detect and it is going to be impossible to manually equalise as well.

The big question is are there alternatives which give better results than equalising systems which often give results worse than just guessing. As the DAV decided the benefits of minimising extension are clear whereas the benefits of dynamic equalisation are effectively non-existent so redundancy is the choice giving clear benefits.

Jim

I haven't picked up the Long and Gains anchors book in a while.

I suspect the loading variability among successive drop tests would be much higher with "equalizing" configurations like the sliding X rather than the fixed powerpoint of something like a cordelette.

Um... go do that. It does not say what you think it says.

Nope. Look at the chart in the back, and the data series labeled cordelette unequal arms.

GO

I did note that and used the term"outlyers" in my synopsis to identify the issue even though I wasn't prepared to make my post much longer by discussing it. The narrow error whiskers on the sliding X unequal suggest that these outlyers were not included in the stats, only discussed in the text. However, those stats must be those of regular sliding X tests because, for the sliding X with clutch effect manually eliminated, the average result is lower (as low as the equalette).

Of course, not having the raw data, it's hard to gauge what an "occasionally extremely high" sliding X unequal result might be compared to the "regularly low" ones and compared to the high and "generally highly variable" cordelette unequal results.

Interesting that you should say that this question mark over the sliding X results might send you running back to a static equalization option when the equalette was clearly shown to have superior equalization with no outlyers.