Thing thing about combative type systems, is, as has been talked about, they are PRACTICAL. They strip down all of the showy stuff-the things I were taught were brutally simple; essence on brutal. The concept is simple; when attacked, be the aggressor. You fight with everything you have, because your life literally depends on it. One thing to do is keep the guy talking-then strike when he is in mid sentence. Keep on hitting, kicking, whatever, until he is on the ground, not getting up.
Again, it is a brutally effective system, designed for fighting and incapacitating. The idea is that, once down, he doesnt get back up again. You have to have that mindset though; I am potentially going to kill this person. But, he may be wanting to kill you too, so it comes down to who is more aggressive.
Granted, thes situations are EXTREMELY rare in our every day world. But, that one time you need it, hopefully you have it.
Not taking anything away from the martial arts, as I have studied them myself; but, they are largely ineffective in a real fight. Kicking anywhere above the waist is largely a waste of time, unless you get lucky. Particularly to the head. You have to get the distance right. And, if the guy has ANY idea what he is doing, he is JUST outside that range. Besides, once you've taken your stance, you've given yourself away. best to not let someone know you are going to unleash on them-surprise & violence of action should pull you through!