. . . came to me while reading a vast number of embouchure posts on woodenflute.com: more control of IT than the upper lip is the key. I tried raising my lower lip instead of peaking my upper lip down for low D and a few other notes in the first octave and, voila! It happened. I recall reading someone’s disertation about making a bird beak of the upper lip curling it down over the lower one and I couldn’t really do it. Raising the lower lip – a snap!
Well. I hadn’t thought of it as a bird beak, but I can see the reason to such a description. GOOD NEWS: Yes, you can do it! Simple, use the air pressure provided by your own diaphram. Your airstream can be used to fill out your upper lip, and the muscles of the upper lip can then be used to shape the lip, just about anyway you could want. It’s easy. Give it a try.
Back on topic, yes, the lower lip does most of the work.
I liked a description that the lower lip acts like the spout on a pitcher, pouring the air where you want it. Seems to me the lower lip should stay relaxed and flexible.
Years ago, there was a publication in the United States known as Mad magazine, which featured a character by the name of Alfred E. Newman, who asked, “What, me worry?”