Yikes, I don't take advice from random pet owners, or random vets for that matter, it'd have to be someone long experienced keeping, breeding or treating reptiles for me to consider it. If this guys snakes are constipated on the regular, I'd be questioning his husbandry and thinking he's likely creating more problems than he's fixing. I've never had a constipated snake and don't think it's very common if properly kept/fed.