May 19, 2012, 2:59 PM
Registered: Dec 3, 2002
Unfortunately, no. I'm reporting the results of a private communication from a third party. The chance that the study met any standard conditions for statistical validity are, I suspect, small. For all I know, he made twenty placements and one pulled, although the impression I got from the letter is that far more placements than that were involved.
I wouldn't ascribe much significance to the 1 in 20 number, although it is nice to have something to wave around when people speak about bombproof cam placements. I wouldn't be even a little surprised if 1 in 20 was right for small cams.
What is significant is that someone with enormous expertise finds, on experimenting, that he cannot always predict that a cam placement is good. That is all any beginner (or any expert, for that matter) needs to know in terms of calibrating their own approach to safety questions.
(This post was edited by rgold on May 19, 2012, 3:03 PM)