Maybe I'm missing something, what does a Cornish bring to the gene pool? Why wouldn't any heavily bodied meat bird do for one of the parents?
I'm new still but remember you want a FAST GROWING meatie. You dont want to feed it for 4-5 months to reach slaughter size. You also want it to convert that food good not a bird that will eat but not pur on weight. So maybe it brings that to the table i dont know anything about them.