As the irons get longer then, imploy more of a rotation of the shoulders through before impact. It is easy to try to hit them harder with the hands to generate the power, but as the club gets longer, that gets harder and harder to time correctly (as compared to the shorter irons). So the idea of hitting better longer irons is to use a longer swing, longer arc while maintaining better control of the hands into impact. Think about the trailing shoulder returning past square and as far past as you can before impact. My impact/wall drill gets you this feeling. It should feel as though the leading shoulder is higher then the trailing, or the trailing shoulder is lower...what ever you like to think about...both work. (I say it this way because you will have a hard time thinking about 2 things, just pick 1).

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I'm a golfaholic, no question about that. Counseling wouldn't help me. They'd have to put me in prison, and then I'd talk the warden into building a hole or two and teach him how to play. ~Lee Trevino