Ok so Tiger’s win has got me a little reinvigorated in golf. I understand there is more than one way to skin a cat and it is not my intent to disparage other swing theories. I do think this little nugget may help though.
We have all seen golfers rehearse their backswing with the club over their shoulders as in the image. Most golfers do this by rotating their shoulders much too flat/horizontal. Or they get in their golf posture and produce a good looking/more proper turn. But almost everyone is missing a crucial link between doing this rehearsal and a great pivot.

Ben Hogan said he liked to stand as tall as possible in his set up position. Let’s take him at his word and do that while performing this. Stand tall with your club over your shoulders, feet shoulder width apart and in a generally relaxed nature. Make a shoulder turn into your backswing. When you do this, it is imperative that your intent is to get the club pointing to the ground at about No more than 6-10 inches outside the target line (looking from a down the line view, <10 inches right of the ball). Remember not to sway to the right. You are turning.

When you do this from an upright position your body is forced to create room for your left shoulder to go under your chin. To me, I get the sensation that my lower spine is kind of elongating while the pressure is put into my right glute. Be careful here though, as I don’t feel a massive weight shift off of my left foot into the right. I still maintain approximately 40% weight in left side/foot. This allows for the proper amount and direction of movement of my left knee. AND I AM NEVER TORQUING MY UPPER LEG AGAINST THE LOWER LEG. THAT IS A RECIPE FOR KNEE PROBLEMS. Do this and keep doing it until you find yourself in this classic, powerful lower body position. It can happen quite naturally/easy.