The best example I have seen using a Cornish X in a breeding project is duluthralphie's toads. This is from his threadReally, i thought those little ones were just the Cornish hens that are the Cornish in Cornish X.
I did hear that the Cornish X was a 4 breed cross.
For the other poster... When you talk about people breeding them it is usually to other breeds to produce a good meat bird without the Cornish X trough rate which equals their issues right? A more sustainable meat bird.
https://www.backyardchickens.com/threads/toad-raising.1152440/
The Toad is a 4 step process,
The first Generation is Cx crossed to CX,, That is known as a frog
Next Generation is a Frog to a Dixie Rainbow, This becomes a lizard
Then the lizard is crossed back to the CX.
That gives you a toad, it is 7/8th CX and 1/8 Dixie rainbow. That little Rainbow gives a bigger bird that does not eat itself to death.
They are huge with more dark meat to white meat ratio. They are not lazy slobs.
Fascinating thread even if you don't raise meat birds.
I hope he doesn't mind me posting a pic of his, but here is an example of one of his processed toads next to a turkey of the same age.