Mack was a different animal. Literally. He was a beast. Loved to hit. Hyde is smarter and not as big. And he accelerates to the second level better.
I remember a game when Webster Slaughter caught a TD pass and took his helmet off before he got back to the bench. Mack wasn't thinking and gave Slaughter a ceremonious head butt while Slaughter's helmet was off. Slaughter gave him that "you're crazy" look while he checked his head for blood.