When I met with Darren at the PGA Championship last year, he was struggling with his chipping game. It turns out that he had a problem in his setup that is common for golfers at every level. Darren stood too close to the ball. It's natural to want to do this, because you feel like you have more control. But from that cramped position, the only way he could take the club back was up and outside the target line. On the downswing, he was really steep--which will make you hit shots fat and thin if your timing isn't perfect.
Once he moved away from the ball, he started swinging more around his body, with more forearm rotation and lower-body pivot. When you do it right, the sensation is like hitting a topspin Ping-Pong shot with your left hand. After two hours of work on chipping, putting and bunker play, Darren felt a lot better. The next day he shot a 65 to lead the tournament.
When I'm too close to the ball (see photo below), the tendency is to pick the clubhead up and to the outside of the target line with my wrists. I'll have to compensate for that later in the swing by flipping my hands at the ball. Remember, a great pitching swing blends forearm rotation, wrist action and pivot to swing the face from open to closed through impact--not closed to open.
On pitches and chips, you want your upper arms (above the elbow) to stay relaxed and close to your sides. The swing comes from pivoting your lower body and rotating your forearms, and allowing your right elbow to fold early.
Notice how my left arm is still hanging straight down, and the top of the grip has hardly moved.