read the stuff again. overeating will lead to obesity in most cases, where there isn't some disease/condition preventing the fat accumulation, in which case the person isn't really overeating anyways.
But, you could think it from the other way - without overeating it's __impossible__ to become obese. . statistics back this up (counting out exotic diseases, elephantinism or whatever). besides, it's a proven method for losing weight: eat less, do more - or inversely a proven method for getting fat: eat more and do less.
(and it doesn't really work like a river that it takes what it needs, it takes what it can and figures out where to put it later).
if you really think you're fat because of pixies or whatever, think then why overeating is overeating. how do you define overeating if not by _eating too much_ ?!? wtf dude.
3 m&m's? it's more like 2 cheeseburgers that's the difference.
The formula works, for performing work, if you don't enough calories you'll starve. THAT is what they were made for and many people were worked to death to test 'em out.. it works for losing weight.