1. Validation - for want of a better word. Learning to play in an era where orthodoxy was that you should be able to buzz your lips meant that in constantly seeking to improve, the lack of a buzz might be a limiting factor. Seems maybe I wasn't too far off the mark and explains why some kids who could buzz real good had trouble playing much above the staff.
2. Refocusing on airflow, aperture, relaxation etc has worked for me.