Hmm impact dials absorb the impact of an attack, which can be released by the user afterwards. Barto's barriers instantly reflect the momentum of incoming attacks. It's no different than hitting a wall. If you start hitting a wall, you might break your hand. In an offensive way he can just shoot barriers, again similar to how you would throw a wall.
A simple, but yet a very effective power. However that already shows its weak points:
1) Barriers can be smashed, so in theory there should be a limit to how much his barriers can handle.
2) Currently I can't see much variation in the ability. When it concerns haki users, at least ones who can use it on a high level and swordsmen/hand-to-hand fighters in particular, it shouldn't be that much of a threat. I mean Bellamy already got a hand on Barto by coiling his arm around his.