A bad tee shot or a water ball makes a double bogey easy to understand. It starts to get frustrating when you knife one over the green from 50 yards out. That's a double for no good reason.
Mechanics are important on pitch shots, but you can get much better results even if you leave those alone and concentrate on your swing shape and your tempo.
"On longer wedge shots, a steeper, V-shape swing beats a shallow, U-shape," says Golf Digest 50 Best Teacher Randy Smith, who is based at Royal Oaks Country Club in Dallas. "Feel your weight forward on your front knee, and pivot around that knee. Try to return the clubface at impact with the same loft it had at address."
As the shot gets shorter, the tendency is to move less with your body and use just an arm swing. That usually produces a big backswing and a short follow-through--or vice versa. "Deceleration is a killer on any pitch," says Smith. "The longer the shot, the bigger your swing should be--on both sides of the ball. Match the size of your backswing and finish, and keep your grip pressure constant. Tighten it during the shot and there'll be a grab in the swing as well."