Now ..one thing in this discussion that has been overlooked is "Neutral Pelvis"...Neutral Pelvis is approximatley 30 degrees...and if you've ever looked at a lot of golf postures they range from 20- 40 degrees of waist bend...Coincidence???
I can not stress the importance of the ears as a marker and the tailbone location as a marker...take a look at the pics.....positioning of the ears....rotation of the pelvis locating the tailbone...