What if there is something to it though? Lets say you had a clutch of ball pythons, from the get go they are getting used to having been handled and acclimated. Much different from one coming from the wild, where it hatches and pretty much heads off on its own and will continue to function on that instinct to survive. Would it not be possible in theory for the part of the snakes brain that functions on fear/defense could eventually get bred out of its system? Since from such a young age they are understanding, there is no danger, only hands, food and hiding.

Like you said, it wouldn't be something that happened over night.

I dont necessarily believe in this, but in theory it sounds plausible it could happen.