With all the unforced errors, mishits, shanks, etc. that Federer has been making off of his forehand all year, he really needs to switch to a two-handed forehand, because as we all know here, using two hands on the racquet is the only way to cut down on unforced errors and mishits. His one-handed backhand is just fine so he should keep that but start using a two-handed forehand. If he does that he should be able to beat Nadal and Djokovic consistently, even on clay. So all he has to do is keep his 90 sq. in. racquet and his great one-handed backhand, but switch immediately to a two-handed forehand and all of his problems will be solved.