it's likely that any given winner is on drugs:
presumably, drugs make people faster.
presumably, some elite athletes are on drugs.
therefore, those athletes on drugs should be the fastest
presumably, the fastest athlete wins
therefore, athletes on drugs should win.
therefore, it's likely that the winners are on drugs.
the only way a clean athlete can win is if he/she is vastly superior to his cheating counterparts before using drugs, or if the cheaters make big tactical errors, or if drugs don't actually help very much.
i say there are three ways ramzi could be clean. first - of all the people who would be among the best few 800m runners in the world if no one were taking drugs, none are taking drugs. second - the drugs people are taking are not very effective for male middle distance runners. third - the fastest people aren't winning, due to poor racing
i don't know how likely any of these scenarios are.