It's not an exact science, because since some cocks simply adore certain favorites or some females are overly submissive they get overbred, so this has to be factored. BUT…..
If you have a cock over a pair or trio of females from one line and they are scalded off in two weeks time, but you put a dual or trio of females from a entirely different line and during their two weeks of breeding you see no damage at all?
THAT is something that grabs your attention. You begin to ponder if this is in some small way a measure of feathering quality on your females. It would be interesting to hear from some on their experiences on this.
I have a trio of Rhode Island Red hens in with a cock bird, been paired since early Feb. Almost all their eggs are fertile, but not a feather out of place on their backs. They are good enough to take to a show. This I like. I wonder, should all breeds have the tighter feathering? I see definite differences between breeds.