I'm a mathematician so I'm forced to think about everything logically. When you apply the rules of logic learned in discrete math and entry level programming, the question of if everyone is on steroids is obvious. Assume: Man A on steroids. Man B natural. Logic: Man A > Man B. How do rankings work? 1 > 2 > 3 > 4 > 5... Extrapolate that to: 1 > 2 > 3 > 4 > 5... = Man A > Man B > Man C > Man D... Applying the associative property, it's easy to conclude that almost everyone is on something. In plain English, the natural guy will almost always lose to the guy on PEDs all else being equal. And, in the general case, there's no reason that everything else shouldn't almost always be equal. Most guys in the UFC, it being the premier level of competition, are winners and not losers. The natural guys lose and consequently almost never make it to the UFC.