I play devil's advocate here only to drive home the point: we need biological manipulation to make sport a spectacle. In fact, I will rephrase that: sport IS biological manipulation. The more pertinent question is to what extent is biological manipulation fair? And can we justify accepting certain forms but not others?
Read any biography of a great man or woman and you will almost always find evidence of the ruthlessness, cruelties and immoralities that arose from their single-minded pursuit of greatness.