ShooterMcMarco
Hall of Fame
Yep -- that's because Federer isn't relying on the direction his arm is moving to produce the WW motion. Roddick / Djokovic are lifting w/their arms to produce the WW. Federer is pronating -- "turning a door knob" -- to create the WW. Thus, he can pretty much swing straight through the ball.
Is the same door knob action applicable to high forehands too?