See that's a good reason to weigh your snake. And I have a TX longnose snake that fasts over most of the winter- he loses weight, but I still don't weigh him- he's roughly 20 years old now, so we seem to make do alright, but he'd be a reasonable candidate for weighing. It still wouldn't change anything though, except maybe it would add to my worry. We've been doing this routine for many years now- I got him as a yearling (c/b) from a pet store, where they couldn't get him to eat & couldn't sell him. (I traded them a well-started easy-to-feed young king snake, an easy pet they actually could sell.)