That's exactly the point the grandparent comment was making though. Because they aren't chronically eating at competition levels is the reason they aren't overweight. They have a high calorie moment, followed by low calorie stretches.
> Your body adjusts its metabolism based on the amount of food you eat as long as it's not chronic.
Suggests that your metabolism is changing, as though your body becomes more or less efficient at burning calories because you're eating more or less. Instead, these guys eat a huge surplus of calories and then go into a deficit to get back to their standard weight.
I'm not exactly sure what their bodies are doing, but I guarantee you my body would get rid of that food extremely quickly before it was fully digested.