I have only slapped a few people in real life, but they all went down. Not sure if that would be the case if I had punched them. Your mileage may vary.
Is Leo saying that there's more energy in a slap than a punch? As a boy my dad open hand cuffed a mule on it's jaw and knocked it down cause it threw me. In old school fisticuffs , long ago, open palm cuffs were for the head and fists were for stabbing the torso targets, to protect the bare hands in unarmed striking, for unarmed defense. It was a means to create space and get to one's bladed weapons. Bas Rutten cuffed opponents to sleep in the unprotected bare handed Pancrase fights in Japan.
