By that logic, it isn't a fact that <ANY athlete in ANY sport, EVER> hasn't cheated, so once again - let's just ban all sport, as basically, your position on this renders all competition pointless.
Agree with all that. My point though, is that once you go down the path of questioning the achievements of people who have never been proven as anything other than clean, on the grounds of 'quickest = must be cheating' then the whole thing is rendered a waste of time.
Calm down.
Nobody is ridiculing you. Just pointing out that, as the answer to a question of the 'greatest' athlete, there is an obvious flaw in choosing a candidate from a sport where, ability is very easily quantified (by points totals), and they sit behind lots of others in that list.
If...
He's the most tested Track and Field athlete of all time, and has never failed a test.
If we can't accept his achievements for what they are, then we may as well scrap all sport.
How on earth could the answer be Jess Ennis, when there are a load of athletes ahead of her, in an event defined by points scores?
She's not even the best of her own era (Kluft was), or the best ever Brit (Johnson-Thompson). Jackie Joyner-Kersee is mile out ahead overall...