you have no clue the kind of matabolism you're talking about there. It isn't even in the realm of your understanding what that man's metabolism is capable of. He could digest pebbles, would suck coming out but he could do it. That guy is on another planet compared to us. He could not however eat mcnuggets as his dietary staple year round. He would not have become what he is on that diet. They talked about what he grew up eating during the olympics, it wasn't fast food.
Plus, it's entirely possible he's trying to get a deal or already has one with McDonalds. It's like bodybuilders telling us they put on 50lbs of lean mass with this new protein shake. You don't beleive them do you?