I'm now wondering, since you mentioned him breeding the colors and breeding profusely, if maybe there is some sort of color problem in chickens? Sort of like how double merles in dogs (and maybe other animals??) is a huge problem. Double merle of course being breeding a merle to a merle. Or maybe not color, maybe something else. Like I know natural bobtails in dogs can cause problems. Not always but sometimes. I think there's a certain gene or part of the disc and sometimes it's fine. Or how the curly pug tail is too tight sometimes/causes issues. And in Nova Scotia Duck Tolling Retrievers apparently the population is so bottlenecked atm it's basically like there's only 15 individuals I think was the number, know it was teens. Like there's thousands but it's so bottlenecked all the DNA comes from the equivalent of that, like there may as well only be 15 dogs, I think. Lack of genetic diversity. They're thinking of outcrossing to Australian Shepherds or spaniels or some similar breed. They have to outcross to save it but.obviously lots are opposed. I think they closed the studbooks too soon. Anyways, back to chickens, I'm not saying there is a lack of genetic diversity in the breed or a problem with colors (because why don't other breedings of the colors have similar results?), but it's all so interesting to me amd.would be interesting to see if there is something similar going on