[MA] Best dirty-fighting style for a callous weakling?

[Anthony]

Originally Posted by Icelander

I've seen tons of fictional heroes who could use speed and skill to defeat much larger and stronger foes with ease.

Which is, of course, something GURPS should permit. However, it will cost you a bunch of points.

Originally Posted by Icelander

Even a kumite national title holder probably can't do anything about a guy twice her weight if he doesn't want to cooperate.

Well, if he has a certain level of skill and physical development. Superior skill matters, and degree of superiority matters, it's just that in the real world there's pretty strong limits to just how good you can actually be, and in general speed is heavily correlated with muscle development anyway (there's a reason track stars and gymnasts are solid blocks of muscle).