Well, yes and no. It is true that men usually overpower women in a purely physical conflict (no weapons other than what you're born with), even when size disparity is modest or equal.
Now if the women is well-trained in fighting skills and the man isn't, it can be a whole different story in many cases. I did a women's self-defense course this time, ran about four hours. A lot of it focused on awareness, avoidance, escape and evasion, but we also spent a good bit of time on hand to hand stuff. About a dozen grip escapes, a couple basic defenses, and half a dozen of the meanest and most devastating strikes anyone can throw.
I had this college age gal there, I'll call her Rana for purposes of the story... she was medium-sized, about 5'7 and feminine of build, but she was an outdoorswoman and amateur athlete and thus strong and quick and well coordinated; definitely my best student at the class. Well oddly enough that very same night (or maybe it was the next night, I forget) she was accosted by a much bigger fellow who tried to manhandle her.... she not only whooped his ass, she whooped it so bad that he lost his pants trying to escape and fell on his face, according to witnesses. :lamo
One of the things I taught her was how to turn an instinctive slap into a palm-heel strike. I then let her practice it on me with some safety equipment... and she whipped my head around and rang my bell pretty good, even through some padding.
Okay now this doesn't necessarily directly relate to the OP and the slap in question, no... that wasn't a deliberate and trained palm-heel strike, but the slap landed her whole hand on his face including the heel of the palm right at the jawline, so it is POSSIBLE she could have done some real damage there, especially if he has prior injuries. Just sayin'.... the only people that know for SURE are Papis and his doctor.
:shrug: