Well first of all they do hair in MMA and if they did a true martial artist would recognize what was about to happen if he didn't let go and killed her a move like this by letting go. Ideally the best way to get someone to release a grip on your hair while they're on the bottom is to put your farm in their throat because self-preservation says to live instead of holding onto hair and dyingonce again, doing it against an aggressor is another thing, the guy wasn't even resisting
its a reason why you don't see techniques like this mma

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