Thanks for your help, Greg! That video helps a great deal. The videos are so full of information that it can be hard to find what you’re looking for – particularly if you’re not intimately familiar with the course or have less than perfect memory. And, of course, the significance of certain points does not always register immediately, so I will definitely bear your comment on “not clamping down the chops” in mind.

I know when the penny finally drops on embouchure and aperture corners, I’ll be thinking to myself “ah, that’s what Greg was talking about! :-)” It’s happened more than once already, and always when my playing has suddenly improved…