In the Madrid final against Rafael Nadal, it seemed that Federer attatcked the backhand side of Nadal. Typically, when us lower level players think of attacking a certain wing of an opponent it is either because we feel more comfortable hitting there, or mainly because it is their weaker shot. I believe Federer did not necessarily attack the backhand but instead attacked that side of the court. In doing so, he made it very difficult for Nadal to find his backhand. For so long Nadal has had Federer's number and it was because he was able to find Federer's backhand (most effectively with a high bouncing shot). I've never seen Federer take a strategy so simple and use it throughout the whole match. That is exactly what Nadal does to Federer and on Sunday, Federer did it better. I guess a very simple way to put it is that Federer hit balls that made it very difficult for Nadal to execute his proven winning strategy against Fed.