You are right that nothing is certain and PEDs have permeated endurance sports. However, I do believe that both Ryan Hall and Meb are absolutely clean. Say what you want about their faith, but I do believe they are both genuine in their beliefs and both would consider PEDs morally wrong.
Hall did run a wind aided 2:04:xx in Boston but also ran 2:06:xx in London. While Meb has not broken 2:06, he is truly world class and can put up consistent results which are virtually unmatched (Olympic silver, NYC champ, and a gutsy 4th in London). If either of these guys has EVER doped then I've lost all faith in the sport BUT for now I do think our sport is clean with rare exception.
Agreed. I pointed out Hall on page 4.