[JimMorrison]

That's actually a beautiful mechanic to differentiate between a "finesse" fighter, and a "brute" fighter. Typically this is done with hard-coded gear limitations, but if you just make heavier armors give a stronger penalty to Dex primary weapons (still a small skill penalty to Str based weapons, too), then you give the player the choice of how much of their offensive capability to trade off for higher protection.