I dont think they would mature as fast as standared but would only be a few extra weeks like mabe 3 give or take a week. They would be perfect for you substained
I dont see why it couldnt be done. i mean they were able to selective breed standards which were about 5 ounces to get up to a pound. just keep selective breeding your biggest jumbos and im sure you could get up to the two pound range one day. itll be worth a shot 

