Think its more a case of define dirty, is what is going on currently illegal or is it yet to be determined illegal. But there is definitely something in the air
Over the last couple of years more and more women are closing in on sub 4 . five years ago low 4 was a good time on the circuit and would have got you attention. Now its the entry point
At World Indoors 3 women made Shelby look an also ran. Anyone smelling the coffee would have had to question the way those three went away from a talented field not once but twice . Even certain medalists had the look of how have I not won i'm dodgy and i'm still getting beat.
Now its outdoor season and Shelby is now with those runners , even possibly better. Think some info was picked up at or after the world indoors ? or was it just better rep sessions improving aerobic performance.
The whole of sport is currently in a very strange place . Froome gets away with what others have been banned for, basically due to money / clout of his organisation. fans from each country think they are the only ones playing fair. Look on this thread US and UK stringent testing etc. WADA etc have shown themselves to be useless. The top cheating athletes are not going to be caught by the testers, its just a game. If you get caught by testers these days its because you've upset someone or not paid your fees. Those in power in athletics have so many skeletons they are not going to sort it out.
Everyone knows Russia was cheating at London Olympics but not good old UK USA etc, but they were trouncing known doped athletes . Russia were caught doping old style. they wont make that mistake again. But they can just say that their athletes are doing more core work now and working more on their aerobic performance.