The inside-out forehand seems to be the favorite shot for many men on tour. Roger Federer basically builds his entire game around the inside-out forehand and so do a lot others like Moya for example. Why is the inside-out forehand used so much by the pros?
Because it allows you to run around your backhand and by playing inside out you do three things (for a righty): you put the opponent in a defensive position; you play into his backhand, normally the weaker side; and you cut of angles. If you were to go for a cross court FH, you are playing into the forehand of your opponent and taking a huge risk on a counterpunch that leaves you reactionless, as you are standing in the backhand corner and your opponent can blast it to the FH corner if he can run it down.
No such risk with and inside out FH, if your opponent reaches it and has a good backhand, he might want to hit DTL, but hitting down the line when you hit from outside the court, which should be the case if a good inside out was hit, means you are actually hitting slightly cross court. If you stand within the tram lines (the doubles lines) to hit down the line means you have to curve the ball from left to right. Automatically your ball is going towards the center after the bounce, so if you counterpunch the inside out forehand, the agressor (the player having hit the inside out) will not be confronted with an angle going wide but an angle moving into the court, so with a few steps he can reach it. In which case he will play a crosscourt forehand moving you entirely to the other side of the court.
Inside out FH thus build in a safe margin in offensive play. That is what tennis is about, giving your opponent a difficult ball to handle, on which by no means he could produce a winner. Save exceptional backhand technique most players can't a winner on an inside out FH, so it is at the same time an offensive and yet percentage type of shot.
