I was once told by someone who had a black belt in one of the forms of martial arts that once you get your black belt you sign a waiver that your hands are considered lethal weapon. Here is Canada at leastMany years ago my cousin (in Poland) was a black belt in some martial arts. He was attacked in the street, took down 3 of the guys on his own, and went home.
3 days later, instead of 3 guys attacking him, it was 10.
Spent a few weeks in the hospital clinging on to life. I'm not saying your plan is a bad idea, as being able to defend oneself is a critical skill...but the problem is these idiots come back stronger, harder, and in larger groups if they know who stopped them previously.
Is that a myth?