I really do love centered riding...... However, my instructor did not teach the reknown "centered riding", but her version was basically the same thing - a soft, balanced, centered seat.
A week and a half ago I rode in a Susan Harris Centered Riding clinic and didn't learn a darn thing!! I already knew and correctly applied all the concepts and was absolutely appalled at how beginner level the clinic was (and I was in the advanced group). I do not recommend her as a clinician.
However, again - I do love the concepts and visualizations in sally Swift's books..... great mental pictures, huh??