Either way AS has to take responsibility for what happened which I think he has. He's got SRAM Red and from the video he shifts with his right hand 2 pedal revs before it seizes. It appears as if he was shifting to an easier gear but I'm not sure. If that's true then that would have moved the chain inward which could explain the chain hopping off the small ring. I don't see where his foot hits the chain but it's a little fuzzy. I do see the bottom of his chain bouncing like crazy and his rear derailleur move forward moments before the lock up.

I've got Red, about to put it on a new frameset, so I'd kinda like to know if that's a problem (not like I'm generating the kind of power they are but one can hope). Cheers