The feather loss thing is interesting to me because I have one with lots of feather damage from mating. BUT. She does seem to be the roo's favorite. And she has loose brittle feathering. I've watched and often he just surprises her, she lets out a tiny squawk and squats, then he sometimes does the fake mating thing but sometimes follows through. I need to watch them all more than I do I think. I still think she's his favorite because of her behavior. She's "easy" for him to mount and since he's been around, she follows him and stays with him more than the others. It's almost like she has gained status because of him. But maybe he doesn't really even try to mount her that much. I'll have to watch.
As Fred said, there are a lot of variables. The study I quoted was broiler breeders in a pen situation with certain aged hens and several roosters, not dual purpose chickens roaming in the backyard setting with maybe one or two roosters. You have to be careful how you interpret the results. That's why I carefully said the hen has responsibilities, not that it is always totally her fault.
I have had a few hens that showed a lot more feather damage than others. When I removed those hens from the flock, I had no more hens with that damage. I've had more of that damage with good hen to rooster ratios than bad ratios, but that was before I started removing the hens with damage and preventing them from breeding. I think age of the roosters probably has something to do with it, but maybe not with mature hens. They generally don't tolerate the young brats. I do think there are a lot of variables.
An example. Kathy's Swedish study reminded me of one I read a few years back. I think it was Dutch but may have been Irish. That study looked at chickens in a backyard-type situation where they could truly free-range. The flock had several hens and roosters, I don't remember ages, breeds, or a lot of other details. But they counted how many times a rooster mated a hen, tracking by dominant and non-dominant roosters. Their conclusion was that the non-dominant roosters mated the hens about as often as the dominant, just not in his presence. So they thought the non-dominant rooster had a fairly even chance of passing on his genes compared to the dominant rooster.
The Swedish study went a lot further and looked at the efficiency of the mating. The results are different.