I think you misunderstand. I’m not trying to get a factual list of everything someone should know. I’m just trying to only do moves on partners that have an understanding of them, and if the technique can lead to big injury, I wanna make sure. This usually only applies to white belts. I’m not gonna ask a brown belt if he knows how to defend a spinning arm bar or a purple belt if they are cool with me trying a Ham Sandwich.

It isn’t a big deal, it’s pretty easy to know what the people you roll with regularly know (vaguely). I know what the white belts I know can safely defend because we roll and are in the same classes. It only matters when you are dropping in somewhere. And if I’m dropping in, I never roll hard and I usually talk more before hand to my partners