That was actually one of my points; that many breeders don't care about temperment or maybe even value and select for agressive temperment. As I don't have high end morphs most of my babies go to pet stores or pet keepers and both tend to value the "normal" docile ball python personality. I also personally don't enjoy cleaning cages for adult females that strike several times every cleaning.
But I accept that everyone isn't going to agree on what to selectivly breed for in ball pythons, I mainly wanted to point out that I've seen strong evidence for agressive genetics on the nature vs. nurture discussion. Given that I personally want to select for docile ball pythons in my collection I believe that not breeding agressive adults will be a significant step toward that goal.