Sorting and probability is just trial and error by using smart choices to eliminate as much randomness as possible.
I find that if I mate 7-8 pairs, I can almost always get a quality increase in the next generation. The more you mate, the more likely you are to get good quality increases, not just 1 point/generation. It's just a matter of how much space you want to dedicate to it.
Opinions expressed in this statement are the authors alone and in no way reflect on the game development values of the actual developers.