Who said anything about doing therapy?
Okay, do I advocate physical harm? Let me put it this way, he has hit you in the face multiple times. You have asked him multiple times to make the adjustment. He has not simply ignored your requests, he has heard them and chosen to reject them. It is a sad reality that some people just don't get the message until something happens that is painful enough to actually penetrate their psyche. An obvious example is a spouse finally packing up and leaving. Not just pretending to leave. "Enough is enough and we are done unless you wake up the fact that I will not put up with your abuse any longer."
I would not put it past an instructor to
demonstrate for training purposes the concequences of disrespecting others and assisting a student in gaining insight as to what it is like to be on the receiving end of like pain as is being inflicted by said student on others.
I get it that he is not a macho guy. My picture of him is more like a doofus. None-the-less, he is an ego-centric doofus who is not really considering the impact of his actions on others. He may truly think he is doing the right thing, but, he truly is not.
He may have a mental scotoma -- a blind spot -- and really not understand what he is doing. Unless and until someone points out to him that his behavior is not acceptable -- and you have attempted to do this in a very kind, but apparently ineffective fashion -- he will continue to go through life 1) handicapped in his relationships, and 2) possibly causing physical and/or psychological harm to others.
I hope this helps. I'm not trying to be a hard-***. I can actually be a very laid-back guy who loves nothing more than a good laugh, but when it comes to people doing harm to others
after repeated attempts to get them to stop, I pull the plug on nice guy attempts and cut to the chase.
BAM! "I have asked you many, many times not to hit me in the nose. You lack awareness and control and are a dangerous training partner. You are selfish and it is clear that you do not care about me or my safety. Therefore . . ."
The BAM! does not have to be hitting him physically. It could just be making a statement like the one in the preceding paragraph. But, somehow, he needs to get the message.
otoh -- you could just go on enabling him.