I’m still confused (a common state with me). Why would it be better to put your knee on the neck instead of the head? Does anyone here know?
That's a good question. I'm not a LEO and know nothing about anatomy or martial arts or restraining violent bad guys, but (as long-time owner of a neck and skull) I think it would be a lot tougher to escape if your neck were being held down rather than your skull.
Better leverage, better motion control (you need to roll to get out from under, the base of the neck allows you to stop the roll) and it is harder for the subject to pull out from under. You also don’t have to apply pressure until the subject starts trying to escape, the fact that Floyd kept talking strongly suggests that significant pressure was not being applied.
This is going to result in a real mess.