I have never had a rooster cause real damage to a hen's comb even though most of birds all have the single / wildtype comb morphology. Inspect more closely to see what really happened.
It seems to be a dominance thing. Recently I had a hen tear another hens comb half off in an ' argy bargy ' over pecking order. I had to remove the hen for fear of cannabalism . She now has a large portion of comb hanging . You only need to watch hens that are on the receiving end of this, they will generally put their head down and hide in the corner. All part of ' coop politics '.