Thanks, all great points! I suppose the confusion can stem from Greg saying “it’s a starting point” when playing in the red. I can clearly place my mouthpiece on two places on the spot where, through zero manipulation, the air stream is straight out. One is way in the red on the top lip, and the other one is way in the red on the bottom lip. The second one makes a sound. But, since it’s “just a starting point” and it gives me the feeling of a free and easy air stream, I try and imagine that same sensation when playing on my regular embouchure after I do several exercises.

The air stream going upwards is a good visualization if it helps to keep the bottom lip from tucking, but I don’t think it should be literally used as the new embouchure for me since my jaw comes up a lot, my teeth have to touch, and so little sound comes out.

I’m still experimenting and trying to discover things. It’s a challenge since the way I initially learned how to play has some deeeeeply ingrained habits.