Wait a sec! So, what is it called when you have chicks that are sexed according to their little wing feathers? I know in some hatcheries there are certain breeds that when a person looks at the wing feathers, there will be a row of tiny pin feathers, and when the feathers are aligned 'short-long-short-long-short, etc, that means girl, whereas feathers that are all the same length means a boy.
Isnt that feather sexing, and a sex-link trait?
I also have a hen that was simply labeled as a Sex-Link. The feed store people said that means its sex can be determined by its coloring as a chick. I do agree that you do have to breed for the trait, but wouldnt all chickens called sex-links create chicks that are sex-links also?