Bent out gate strongly suggests that the top of the sling was on the gate of the top krab. If the gate faced the way you were climbing (i.e. right) and there was something preventing the krab rotating then conceivably you might get the sling moving up and around, then locking onto the gate because the hinge prevents it coming back cleanly.
Total speculation, but can you comment on whether the rock near the bolt was rough, or had any obvious protruberances? |