Several mentioned a couple of cues that have worked for them.
As a general tip, I would as another mentioned, recommend thinking about tucking the elbow. I liken it to the golf training tip, "if you can keep a towel tucked under your arm..."
That might be a bit of over-correction, but thinking about keeping your elbow close to the body will automatically enforce the hand staying under the ball because your forearm will be facing up naturally.
One comment about your video, you actually self-correct pretty well. One of the tell-tale signs of things going wrong is "chicken-winging". That''s when your elbow gets away from your body on the downswing and you get around the ball causing this "chicken-wing" effect. You come through the shot OK. It really isn''t too bad.
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Edited on 6/8/2010 8:17 PM