https://youtu.be/We-nxljgnw4
Physics and Experiments demonstrating GriGri slipping in No-Hands Belay. Head to https://brilliant.org/hardiseasy to get a 30-day free trial + the first 200 ...
A good recent video from Hard is Easy on the GriGri belay device
In another video, he started comparing several auto-locking belay devices and I was surprised to find that the grigri's active auto-locking took much longer to engage than say the Mammut Smart Belay's passive auto-locking.
I was climbing out at clear creek when the group next to us suffered a large rock fall, knocking out the belayer and we credited the safety of the climber to the belayer's grigri and stopped using Smart belay outside but after watching these comparisons, I will likely rethink this
My takeaway was that it CAN happen under pathological conditions (rope in compromised position, and you're standing directly under your climber, rather than it's something to worry about... Like, if you consistently abuse the GriGri, then the 0.1% chance of failure may eventually get you after 100s of abuses. But for the 0.01% of the time that you get knocked out by a rock, the odds of hitting that 0.1% chance of failure are astronomically low. And probably 0 if you were standing back appropriately and don't have the rope sitting a crazy way.