skribs
Grandmaster
The weight on them makes both how to swing them and the strategy/tactics involved different. As a basic example, i cant do an umbrella block with an axe.
Brass knuckles require a different hand position, and different strategies. There are also things you can do with them (block weapons), and things you cant (grab) to make it different from unarmed.
Its risky to create broad categories for weapons like that and try to force them into those categories, for two reasons. First is that any weapon you will conceivably have on you, you should be training with. Second is you shouldn't assume you know, or are capable of using or teaching, a weapon because you are capable of using another weapon in the same "group", which categorizing it like that would absolutely lead people to do.
I'm obviously making very broad categories here. It's a way of categorizing them that makes sense to me. It doesn't have to make sense to you. I even gave you bigger flaws than you're giving me, and you haven't jumped on those. You're not even going to try to use the dagger vs. greatsword argument?
And the reason I make these categories is not necessarily for weapons you train with, but more for improvised weapons. If I am trained in sticks, I can pick up a stick. If I am trained in nunchucks, I can pick up a chain. It's not about what I carry, but about what I can find.
Also, where do guns fit?
Some fit in holsters, others in slings.