I didn't learn this from Einstein, but he opened my mind enough to consider this: in bottom half, against a large opponent who has head and arm, who's trying to smother me, I wrap my overhooking arm around the back of their head and work my under hook to a spot capable of gagging them and then squeeze the shit out of them. I haven't perfected the finish, but it's turned into a great way to force them to move off me enough to get to pdu.