Yes of course you're right about the 2 genes per trait Saga, and it would indeed involve some kind of mutation .
I tossed out this idea without overtaxing my grey matter as to the details and hoping that some more speedy and acrobatic minds could come up with workarounds which would keep everyone happy.
Sort of think tank if you like ...
I heard today that there are around 15 new traits in the xmas kitties and probably more planned for uncomfortably soon, and suddenly felt like a hamster in a wheel. Just when i'm starting to get somewhere with my breeds they become more or less obsolete, to the point that it hardly seems worth trying to breed in new traits anymore