Originally Posted by TheCheese
Imo, the straight arm actually has more room for adjustment. You aren't forced to hit with a fully straight arm on every shot. If your footwork is a little off or the ball takes a weird bounce, you can naturally change into a more bent position. You see Fed do this sometimes.
imo it doesn't. With a bent arm you can extend or shorten the arm. With a straight arm you can only change it into a bent arm (which is no longer straight in a lot of cases) (giving a little room for interpretation of straight arm). with a straight arm if your footwork isnt great or the ball takes an unexpected bounce that puts the ball further away from you can't make the straight arm straighter. but with bent arm you are closer to the ball and can extend if need be.