Would it be plausible that since elite athletes who are tested frequently gain such an intimate knowledge of the testing regimes that they and their trainers are able to develop doping routines that would escape detection?
I believe professional athletes should be allowed to use PEDs, provided they are transparent about their use and the option to play 'clean' still remains an option ('clean-only contests').
I have also heard rumors for years that some professional golfers use beta blockers (or equivalents) to 'moderate their arousal levels'...
Open Netflix -> select Icarus -> watch entire movie -> question answered