I don't know about your advice, sounds like it'll land you in jail in Canada. The worlds different everywhere I understand, but generally speaking even defending yourself in Canada is risky because our court system has a pussy outlook on life.
This happened to me last week, I would describe this as an extremely rare event. This person nearly rear ended me driving because he wasn't paying attention to my blinker. So he gets pissed off and jumps out of his car and marches up to me. He is screaming and yelling, calling me names, and then he started to threaten me.
You see in this situation, a one punch knock out even if I could pull it off is not going to do me any favours, I'd undoubtedly be charged with assault if I stuck around and waited for the police to arrive. I'd probably damage my hand as well.
In that situation I just smiled, I workout every day, I have no reason to be intimidated by average Joe. He threatened to "punch me in the head" over and over, but from his distance and body weight, it'd be so heavily telegraphed I didn't see him standing a chance.
In this situation, I became the intimidating one by smiling and not saying anything. If I'm not afraid, if I do not show I'm intimidated, I likely have an ace up my sleeve. He couldn't understand where my confidence was coming from and why I exuded pleasure in the situation.
Needless to say, all he did was break out into a sweat and get back into his car, never to be seen or heard from again. I didn't have to run or fight, I just made it very clear I would accept any terms he decided to bring into the situation. If he is in control, then he knows if he loses the fight it's his own damn fault. I think he left to protect his ego, because he called me a 'fag' one final time before he sped off lol
I think this tactic can work in some situations, but not all situations. You do not have to be physically larger than your assailant to make them second guess their own abilities with a simple smile and demure expression.