The question I essentially ask is why you think drugs plausibly explain your characterization of Keino's scenario. Not the mythical high-octane oxygen vector drugs and methods like EPO or blood transfusions, but the low-octane amphetimines and other stimulants made popular with the East Germans. Do you have a precedent? In all your arguments and examples, do you know of an elite athlete that (bound to their sickbed) achieved these kinds of outlier personal best performances at altitude with the drugs of the '60s? The East Germans, the Russians, or the one British runner never showed this kind of outlier at altitude. Do you see my scepticism? 3:34 is slightly faster than 3:34.91. 3:33 and 3:35 is not 3:27 -- this is a stretched and distorted perspective. From an all time perspective, 3:34.91 (2489th) and 3:33.1 (971st) are slow times, which might be some seconds faster on today's tracks with today's shoes, and faster again with a more specific training. Since it was the 1960s, before going metric, we should also take a look at Keino in the mile, where he has comparable times at lower altitudes, 3:53.1 in Kisumu in 1967, and 3:53.42 in London in 1966. Given that, a similar performance in 1968 at altitude is a smaller outlier, and within the bounds of a natural three year progression. Let's take a quick look at Ryun. Outside of his sole 3:33.1 performance, his next best 1500 is a 3:36, and he rarely got below 3:53 in the mile. He only has two comparable mile performances, in 1967 and 1966, and could never achieve these times again. Do you find that implausible naturally? So Keino produced three comparable performances, with a couple second gap to the rest, the same as Ryun. And competing often doesn't mean you've realized your potential. Look at the hit and miss career of Webb - a career 1500m/miler, trying to run fast every year since his high school record, he finally pulled it all together one year in 2007, achieving performances in the 1500m/mile two seconds faster than ever, never to achieve them again. Is that plausible naturally? The training of the 1960s wasn't all that advanced, particularly in Kenya, as we can see with Lydiard dominating the 1960s from nowhere with his "new" method of training, something that improved in later years with event specialization. Even competing often in the event, Keino may have not realized his potential. Your whole viewpoint depends on a set of beliefs: - You don't believe this is possible naturally - You believe he was too sick to run at his best - You believe that drugs of the 1960s are a likely explanation for personal best times at altitude Since you struggle to build an affirmative case for these beliefs, the rebuttal is the opposite beliefs formed with equal foundation: - Natural is plausible - His illness played no role, or perhaps even a positive role with a forced recovery - Drugs of the '60s is not a plausible explanation