Steve,
Ran across this video this morning and thought it was a great summation of what it’s all about and a clear message that it’s not physical, it’s mental.
It is physical in the fact that we must move our embouchre in coordination with the air column and interact with the air column; but it’s not physical in the sense that what you need to do is play the exercises in the order presented and you will develop physically into a monster player.
The exercises, especially in the beginning, are meant to help you discover new sensations and let go of old concepts about playing.
One thing I did in the beginning that helped me a lot which Greg mentioned in one video was to listen to Windwork videos on my way in to work–I have about an hour commute each way so I would listen to the videos as I drove in.
I tried to surround myself with the concepts [still am, obviously… :)]. I think that helped my mental state as I approached playing the horn to where I was thinking about the various WindWorks concepts and not my preconceived notions, old sensations, habits, etc.
In time, I lost those old habits and am replacing them with new.