I didn't start with a Leghorn roo, my first was RUG - "Rooster of Unknown Genetics" - but I have bred Comets, and they remain part of my culling program.
Fortune Favor your efforts
Anytime you breed a hybrid, results are unpredicatble. With a Comet, where the hatcheries don't even agree on what the parent stock is in terms of breed, the results are even more unprdecitable.
Answer Yes, its been done.
Answer You get a non-Sex linked layer of some sort. It will likely lay...