Normally the 2 weeks on clay in Paris are the most gruelling test of mental and physical resources in tennis, with the best of 5 format and the long matches. I find it interesting, that Federer withdrew from Hamburg after Rome, and played Halle after Paris. He said himself, that he hadn't a chance to win at Hamburg, and withdrew. So the Rome final must have been a brutal ordeal, that left him exhausted, although Rome was played mainly over best of three. Nvertheles i am surprised, that he took the Halle tournament, which turned out to be more challenging than expected. Maybe not the ideal preparation for Wimbledon.