Paulie doesn't have feather fists, he has serious hand problems. In reality, he's probably capable of being a puncher due to his speed, but he doesn't sit down on his shots.
Roach probably addressed the way he wraps his hands and worked on his explosiveness in training. It's just one of those instances where it's "funny" to clown him for being a light puncher, when most people know the reason why.
Comment