With your last phrase, you clearly show your limited ability to think.
I can't here give you some lesson about methodology, but I need to point something.
The natural qualities of every human being, when we speak about "running", bring runners to individuate from when are very young where they can succeed at the moment. So, we have boys and girls that, without training, feel better running something longer, and others who discover are better in something short and fast.
The reason because a boy/girl is already fast is because the percentage of fast fibers, and, of course, the power of the nervous system. Also the morphology is important : short boys/girls develop their muscle system faster than long boys/girls, and spend less time for reaching performances near their top, because their chronological age doesn't corrispond to the biological age.
Therefore, everybody can have a specific duration at top personal level, using a well defined percentage of intensity. This means that for some athletes the best "hypothetical" distance can be 300m (not 200 and not 400), or 600m (not 400 and not 800), and so and so. But, if those distances don't exist, the athlete must use a "compromise" in training, that normally is so train for the superior distance.
Why this ? Because, under methodological point of view, it's very much more effective to EXTEND the intensity, than to QUALIFY the extension.
Whern you speak about Snell training like a marathon runner, clearly you show that don't understand anything about methodology. Running 160 km per week, sometimes with 3 hours continuous run very slow, is not training like a marathon runner. In his marathon (Snell tried almost every year, for controlling his resistance) his times were 30 minutes slower than the top marathon runners of today, while his times in 800m could be at the top still now. This means that he NEVER trained like a marathon runner : he trained like a 800m runner, having some session of long and slow run, that NEVER could make of him a runner for 5000m.
Snell was 1,79 tall for 80 kg, and his main quality was not the aerobic, but the Muscle Power.
You are totally ridiculous when write that all the best were doped, and clearly don't know what are speaking about, but are prisoner of your obsession. You don't have any idea about what it means to have talent, and till where the talent can bring an athlete.
The fact that somebody used doping doesn't mean that all used doping, and the fact that the number 5 in some event was acclared doped doesn't mean that is not possible to have other 4 clean athletes faster than him.
And this for two reason :
1) The advantage doping can give to the performances are largely overestimated, and depend on individual characteristics and the level of training they had before doping
2) You suppose all the athletes have the same talent, but is not like this. So, talented clean athletes can run faster than doped athletes with less talent.
But when somebody is mentally sick, being subject to hallucinations and seeing doping everywhere, it's difficult to follow a line of reasoning based on facts and not on suppositions.