Great post by the OP.
Has anyone noticed that Rupp and Farah are completely ripped, way beyond how Geb or Bekele or any other distance great looked? They are all skinny as rails, of course, but even then most will have some subcutaneous fat, not the striated appearance of a body builder...or Rupp/Farah. The only comparison I can think of for that look is Ezekiel Kemboi.
Is there a "special sauce" that takes someone from the 8% body fat of most elite men to the 6% or less of Farah and Rupp?
Let's just say that thyroid-boosting is a wonderful thing.