Personally I think it's stupid that you can swap from another special to black hammer for a boss fight and endless stun lock the boss with the 3 bullets you have left. But I don't entirely agree with the black hammer changes. I would lower the impact so you can still constantly proc the White nail perk for infinite ammo which makes the unique and worth chasing. However the damage output would be lowered greatly and bosses couldn't be endlessly stun locked.