[Johan Larson]

The problem I have with this advantage is it doesn't really correspond to anything in the real world. It makes you better at hitting specific parts of the body, but not vehicles or static targets, and with anything from a fist to a sword to an arquebus. It's hard to imagine what sort of training regimen would produce such an effect. If you're better at hitting with a specific weapon, that's skill in that weapon or weapon class. If you're more precise in general, that's a boost to your DEX.

If a player were really keen on targeted attacks, I would allow taking targeted attacks as maneuvers, but each maneuver would be with a specific weapon against a specific target.