Well, my take on feather sexing as a priority in breeding delawares is kinda more like
than
While it would make things simpler in sexing - exactly what other genes are you selecting against that you need in this new breed, with enough problems to keep you busy for five years?
Genes don't exist in a vacuum. Hatcheries don't give a fig about quality of the chicks produced.
Yeah, spare roos are a pain. But you cannot sort for quality of roo by culling most of them at hatch. You will miss birds you need for a breeding program. Now if you give no fig for improvement, then keeping a hatchery quality flock that way shouldn't be a problem.
If you're one of the folks on this thread looking to improve the breed you can't take the easy way out.
It's easy enough to tell del cockeral from del pullet relatively early - great silly red combs are kind of a give away. And shortly after that the ones with very bad combs will show up - with sprigs etc.
But if you cull most of them with the handy feather sexing gene initially you'll likely miss some of the keepers you need to improve things. Not to mention is that feather sexing gene connected to any other allele and gene you NEED, for better dels? Genes don't always affect just one loci. They can add up, cross over - make things better or worse. How many of them work together isn't all that well known.
Type - body first, color - leg/feathering, then comb.
That puts feather sexing in fourth place after getting combs sorted out.
Priorities matter when establishing a line.