The guy in black has fight experience.
As far as the slaps go, in the old Pancrase days they would use open palm strikes because they had a rule set that didn't permit closed fist strikes to the head....it was odd....anyway dudes learned they could easily knock guys out with the base of the palm....it's the same technique they use now in the eastern European slap tournaments...I'm not saying that's why he was using them, just that they're not useless.