>In short, this stuff is 90% magic trick.

I would say, kinda but not entirely. IME as a practitioner in my youth, I would say that breaking the mental barrier to throw a good punch is a thing that needs to be broken as part of the martial arts training. Another thing that a good training gives you and not many people understand is the preparation to receive a punch, not cower in fear and still keep a sound mind to try to recover and react.