I've experimented with leveling groups of rogues and warriors, and like others mentioned, it is fine for pve. Pvp has problems though. Even if you could perfectly copy mouse movements, any stun, snare, or anything else that gets your characters out of sink will ruin everything. Just think. What happens when you get feared?

Leveling a melee groups is on my list of things to do, but it will be strictly for pve.