Great on grass, good on hard court, mediocre on clay, is Federer the new Sampras?
The unbalanced schedule allow players to dominate and rack Slams, even if they can't win on the only surface that truly requires talent: clay.
Unless Roger wins the French Open, he will be lumped in the same category as Sampras: an incomplete player who lacked the talent to win on clay.
At the moment, neither Sampras or Federer can be considered as the greatest of all time.
I'll look at it from you're prespective. Nadal won 2 French Opens beating a mediocre Fed in the Semis once and a second time in the Finals. He also beat Fed in the Finals of Monte Carlo and Rome. What you are saying is that Nadal is only a slightly better than mediocre clay court player having only beaten a mediocre player for his titles.