the problem with cloning is it will never produce anything better than what you are starting with. best case scenario it will produce the same thing, but probably with some defects.

the idea is to randomize combinations so that there will be some really bad combinations and some really good and you discard the bad ones and multiply the good ones.

but there is a limit to how much you can randomize things. like race-mixing is the ultimate in randomization but you can only race-mix maybe 2 or 3 times before everybody is of the same milk chocolate race and you can't "race-mix" anymore.

so it should be fine to in-breed 90% of the time so long as you also occasionally breed outside of your own genetic pool.