More Efficient Power = Distance
Power comes from winding the shoulders first, from the top down, while resisting with the lower body. What I mean is this: on the backswing, use the shoulders to wind the arms and club around the spine as you resist* with the lower body. In other words, hold your lower body still while the shoulders turn first to get a head start. Eventually, the hips are pulled around a little by the shoulder turn. (The hips do not move on their own or slide at all toward the back foot. If you want power, you need resistance.)
Now, on the downswing, you unwind from the ground up. Start with the hips, pulling the arms back down in front of the body as you keep turning. The faster you unwind, the farther the ball goes—just like throwing a ball.
The above paragraph has a lot of good stuff. Once you’ve learned these movements, you will hit the ball very far with all clubs. There is no magic trick other than practice and repetition.
—Ross
*One great way to “resist” is to keep the back knee braced inward as your shoulders wind up on the backswing. Try to keep 60% of your weight on the front foot during the backswing. You’ll be able to return to the ball much more easily.