My 21 cents again.
1. If you breed even a pure species to improve upon it, then you are seeking to change the status quo and thus... you are not truly satisfied with it... or else why seek change... thus.... it is not such a far leap to consider my idea of hybridizing to further that change... in effect... to speed it up as the genetic pool becomes larger with hybrids and thus the possibilities increase as well. Arguing over how much to hybridize and how much the snake must look like a hybrid versus a corn marginalizes the corn morphs we already have because of hybridizing and the genes that are utilized for certain morphs that came from other species.
2. I've heard that pure cornsnakes cohabit fine. Its those that have a bit of something else hidden in them that don't cohabit quite so well. If this is true, then one would want to cohabit cornsnakes to eliminate or figure out which cornsnakes exhibited a non-corn behavior. In this manner, one could at least select for cornsnake behavior... even if one were to continue to keep the noncornsnake genes for color/pattern, etc. for creating new morphs. For me, it is a matter of selecting out the traits you desire to keep as well as the traits you desire to add. There is no point in making a hybrid that does not give some new phenotype to a corn or corn hybrid. Any thoughts or clarifications on this anyone?