It takes two to tango, as the saying goes. What that means is that one hen may accept mating in a manner different from another, resulting in different feather wear patterns.
I have two roosters. They have divided the flock in half, each roo looking after and mating his own harem of around eight or nine hens. If there are any fewer hens to rooster ratio than around 1 to 10, the hens will receive much more attention than they normally should be subjected to, and they can get pretty worn and frowzy.
However, I still keep the rooster separate from the hens except for a few hours in the afternoon when they all get to party. This is actually a popular practice as it reduces stress on hens and relaxed hens lay better. There is also less opportunity for mating and less wear and tear on the hens. It still provides ample opportunity to fertilize eggs as one mating can produce sperm that will be active in the oviduct for up to two weeks.
My two roosters can still watch the girls all day, regardless if they are with them. They are content and enjoy free ranging with each other when they aren't looking after the hens. They all roost together at night.