That is a good point. What gave me the idea was this image from Total War: Attila http://i.imgur.com/zAf0qt1.png The one I'm talking about is the one on the far left (It's supposed to be a Jute) where he has his shield equipped, but the length of his axe makes it seem more like a two-handed weapon (It's not quite as long as a Dane axe but still a good length). I was also inspired by the long axes in the Mount & Blade DLC Viking Conquest (If you haven't played it, there is a weapon called a long axe that behaves similarly to a longsword where it's more efficient with two hands, but can be used with a shield which makes the swinging speed slower. There's also a goidelic version as well). The other source of inspiration is, of course, the bastard sword. So maybe instead of it applying to two-handed weapons it could be it's own category of long weapons like a compromise between one-handed and two-handed. That might require it's own skill tree though which I don't think it's possible of creating a completely new skill tree through modding alone.