I'm just reading this excellent book : How to be a spy
I was hoping to learn a couple things about self-defense, awareness, what have you... I haven't learned much that is very useful, but it's still a great book, very interesting, and providing insights about how things used to be during WW2.
Anyway, the reason I'm posting here is that on the section on close combat, they mention such things as "Do not kick above knee height", or "Never go to ground if you can help it". So yeah, the old japanese masters had it, they had it in '44, and I've read and heard it from pretty much every serious self-defense instructor I've gotten material from. It's probably got something to it, then ! :)