I just got out of a gi-based seminar that was almost all chokes, and wooooo... I was feeling a bit floaty there at the end even before the chokes were sunk. Reaction time was definitely shot. I've never choked anyone out or been choked out but I've made the "hurk" noise plenty of times. Usually when someone gets the windpipe but not always.
Its not a matter of pain. Its a matter of the blood being cut off from your brain so you pass out, whether you like it or not.
We'd been drilling arm triangles for 1/2 hour, so yeah... he was probably a little lightheaded to begin with. I've made the hurka noise pretty often, too, but I've never been at risk of going to sleep. I always see lights when my brain gets a little O2 deprived.
Its so easy with blood chokes to think you're getting out of it and then suddenly think... oh no... actually... I'm n... ZZZZZZZZZZZ.
