I’m writing this just in case it helps someone else.
I have been going through the early lessons of the Largo Stage again. Body’s Concert Hall breath, Oooaaah – all good! But as soon as I raise my tongue to stop the air before releasing it into my (neatly folded) tissue, my throat blocks up. I tried to lower the back of my tongue; couldn’t do it; I moved my jaw backwards, forwards, up, down; didn’t help. Then I saw a comment on another website along the lines that the throat is always open when humming. (Ahh, humming? Yes, Greg does a lot of that!) I added an extra little step to “my personal ooh aah procedure”: when picking up the tissue, I hum and tongue at the same time; throat stays open while doing this; good news! Then I stop humming but carry on tonguing, and it’s suddenly working. Success! Hurray!! 🙂
Clearly, this is no way of playing the instrument, but I am more and more able to get that feeling even without the initial humming.
If this against the rules of “proper wind-working”, I’m truly and deeply sorry, but as I said, I’m hoping it might just help someone else.