Cavechat.org

Yes, I am not saying we should all stop using single-bolt rebelays. I agree that the anchor above is generally an adequate backup, provided that it is of good quality, that there's enough rope in between to absorb shock but not enough to stretch far enough to hit something like a wall or the ground, that slack in the rope is minimal so the fall is not too far, and that you don't hit anything when you fall, drag the rope over something that could cut it, or put you somewhere unsafe or impossible to climb (like in a waterfall or under a constriction that doesn't fix a person).