I have nothing other than personal experience as far as keeping multiple snakes in one cage and that is several years old.
It interests me that so many espouse ONE way of doing things as the ONLY way that is proper when NO other way has been tried.
I'm not trying to convince anyone of anything, personally I figure what you do with your snakes is up to you. I just like to know where these people who so freely give advice get that advice from.
It seems that most of them have had, at best, less than half a dozen snakes and have not had them for more than a year or two and are relying on large scale breeders or lousy pet shops to give them the information they then pass on, never having verified any of it, just saying it because someone who does it that way said to.