High levels of testosterone rob one of ones hair. If Pete was able to dunk a basketball, I would pledge that a large part of that was due to his enhancements. Look at pictures of him when he was around 13. Stick legs.
Later on, he went to the longer pant that we now all use, and I swore he used those pants to hide the orangutang legs that he had "developed".
I think Federer's enhancements were more in the way of stamina and quickness. Pete went for power.
And Federer's sudden out of nowhere concentration?? http://www.youtube.com/watch?v=XE5uv7j25Us&feature=plcp
I would wager that he is fully hip to these.