I see your points, and I think that Phelps is a freak and the majority of folks shouldnt try to replicate it. But for him, I think the diet he eats is perfect! Considering that he will likely exercise for 30 hours or so weekly, with a vast proportion of that being high intensity work - and considering his bodymass, energy expenditure and genetic predisposition for leanness and nutrient partitioning and utlisation - the diet does what it should! fuels performance, fuels recovery and ensures optimal bodycomposition. I would imagine that at reduced training volumes, if he continued to eat that way, he would see a reduction in health.
I guess what I am asking is how far would you go to reach your goals? Whether it be bodybuiling or performance?