However, I do have to say, while doping is certainly cheating and by no way would I advocate doping, but for a sport like tennis, does it actually help? I mean as my private coach would always say, tennis is 80% mental, so no matter how many years of doping you have, if you can't mentally win an important or if you don't have good technique or whatever, you aren't going to win. So while doping is certainly a serious offense, honestly, if a player couldn't beat a doper, I doubt it had anything to do with the person being a doper, but rather one just being mentally stronger or just a better tennis player. If I remember correctly, back in 2007 when Roddick was asked about Canas' return to the game, Roddick said something like "it wasn't like he didn't know how to play tennis" and I think that is exactly right about dopers. So again just to reiterate my point, while doping certainly is cheating and any player caught doping should be punished heavily, I don't think it really truly has a great bearing on our sport of tennis as it does nothing for your techniques, gameplay, shot selection and mental strength which are all much more important than the physical aspects doping can "help" with, so any player losing to a doper IMO has nothing to do with the doper being a doper (unless something way out of the norm is evident like the guy is hitting 200 MPH serves, lol..)
I agree only to the extent that a player performing well with doping would have good techniques, gameplay, shot selection and mental strength. But, the physical advantages that PEDs give, can impact the outcome of a match in a huge way. If you are able to put on 8-10 KMPH on your serve and grounds trokes, you become a much better player than you were.
I know this is probably a wrong example in this thread, but it meant just as an example of my point. I am not making any accusations.
Nadal's USO win had a lot to too with his improved serve(especially speed). Sampras won his last slam, after taking an insane amount of pain killers for his shoulder pain caused due to the serve.
All I am trying to prove by this is that a "small" physical benefit is in no way a small factor in determining the outcome of a match.
There is not much differentiating the top players. PED's will produce that difference.
Edit: And this is only considering the difference caused in "strength". Stamina, among other points would also make a difference.