After the Belfort/Jones incident with the organization literally covering up a dirty result to save a main event, Lance Armstrong testimony and doughy. Out-of-shape fighters popping for stuff, nobody gets the benefit of the doubt anymore. UFC quality fighters in the lower echelons might be able to compete with god given genetics, but the elite in any division are comprised of those who’ve learned to beat the tests and those who have not.
Pick and choose your favorites as you will, but never assume a fighter is clean on the basis of never failing a test. Yes, we’re at the point in athletics now. Kind of sad, isn’t it?