That is an unproven & debatable subject. My general view on it is if they seem to want to do it, help them out and go with it. I don't have any snake species at the moment that naturally brumate. Just my beardies. My male did a kind of half brumation this year.
The most informative thing I have heard on the subject was from a guy I talked to for a while about diamond pythons (morelia spilota spilota.) They have long been considered a hard to keep species by many, and this guy has had great success with keeping them and breeding them. He has a female still breeding after 23 years. They are found farther south than any other species of python. And he cools his breeding adults pretty hard during winter, and all of his sub adults and adults get lowered temperatures.
Allot of the problems associated with diamond pythons have started being associated to a mysterious condition that was coined Diamond Python Syndrome (DPS). And some of the new thinking now is that most of these people who have experienced these problems, were keeping their diamonds at a warmer temperature similar to most other python species. And this was in effect, speeding their body functions and decay. And those who weren't, and giving a more natural winter, weren't having the same problems.
So, most likely, it is beneficial to animals who come from these types of climates naturally. And the real key is to watch the animals behavior, if it is slowing down, sleeping and hiding more when it would normally be out, just go with it.
And you should see some of the weird reptile related words & latin names that are in my dictionary
