Of course it does. Haki is stated to be an armor around you, it's a force that surrounds your body or an object. When you coat a bullet, or an arrow, or your own body with the invisible variant, you're basically just surrounding it with Haki. We saw with the Admirals that it's possible to project your Haki ahead of your body. Law could have simply projected his Haki ahead of himself and around his arm, the same way it's around an arrow or bullet or fist when it's the invisible type.That doesnt make sense....