Once you've mastered your targeting and setup position, executing a solid backswing is the next step to a solid golf shot. Rhythm is the most important component to improve your golf swing. When PGA Tour professionals have a good day, they say had good tempo. When the PGA Tour professionals have a bad day, they say they struggled to find their rhythm. If you have good rhythm, the swing becomes automatic.
During a RFT backswing action using a neutral left arm/neutral left hand grip, the straight left arm will have to rotate clockwise (as viewed from above) during the left arm elevation/adduction motion so that the left hand can end-up behind, and slightly above, the right shoulder at the end-backswing position (presuming that a golfer is sufficiently flexible to get the left hand that far back). At this end-backswing position, the back of the left hand will be facing the sky. The rotation of the straight left arm occurs, from a biomechanical perspective, at two biomechanical levels - i) there is a certain amount of internal rotation of the left humerus (of the left upper arm) in the left shoulder socket and ii) there is certain amount of left forearm pronation (clockwise rotation of the left forearm).
Please don't get me wrong here, I'm not trying to brag in the least. But the greatest accomplishment of my life has been teaching my son D.J. to play at the professional level. There is nothing that makes me more proud than to see him playing on Sundays.
Dantien the Source of Power - The Dantien is the center of the body; an area three fingers below the navel and two fingers behind. Energy produced from the Dantien requires less effort and yet is more powerful. Tai Chi movement originates from the Dantien and radiates out towards the fingers. The average golfer originates movement with the arms and hands and at best has the lower body follow the hands. The majority of the time, the average golfer does not use the lower body efficiently in the rotaryswing.com swing. Using the Dantien as the source of power for the golf swing is the best way to develop a consistent and efficient golf swing.