What is the science behind feeding charts?

Hey all, new corn snake owner here. One thing that I truly have not been able to get a straight answer on is how much I should be feeding my corn snake. It seems there's multiple, often conflicting, methods floating around so it's been difficult for me to gauge which I should go with and why. So far, I've been aiming for 15% of his body weight every feeding, and that seems to be working, but if there's something better I want to do that.

To my main question: I've seen several feeding charts, particularly this one (you know the one), get posted on here often in response to feeding questions, but I was wondering if there's any actual science or evidence behind this recommendation or if it's just based in anecdote and dogma. Like the only listed source is "Admins of Corn Snake Care and Genetics", which is basically not a source lol. Other charts I occasionally see get posted also seem to just be from Facebook groups. Are there veterinary guidelines on this or are we kind of on our own?