The thing that triggered me to write this is actually shaping - head shaping specifically. For over 10 years I've been trying to get my head right using all sorts of angles conscious efforts, 'shapes', rules, you name it - but when I glance at the mirror its never natural.
So my new dance guru tells me to use my body to shape my head! What? There is a natural anti-clockwise torso rotation when you move forward in PP - thats the rotation that works against your hip rotation in the opposite direction. If your head stays - where its supposed to be - on top of your spine and does NOT rotate you end up with a natural shape. NO head rotation at all, its all an illusion and a yin-yang thingy (except perhaps a tiny one because your eyes want to see where you are going).
I'm a little late here, but I just had a head/neck breakthrough last week too... and it seems very similar! My coach has always said that you cannot dance if even a pinky finger is tensed up. Well, last week, I couldn't figure out why I wasn't able to move as much as I wanted to at practice and my partner suggested that I just let my neck go, not try to keep it in any particular place. That did it! I felt so much more relaxed, I could move even more than before and my partner said it felt like he had ten more pounds (of potential energy?) to play with

OH! and it looked SO much better!
All of a sudden your head starts to respond to your dancing - its not a decoration at all, its an important tool to assist in motion, often as a stabilizer.
Seems you had a similar epiphany!
[And nice to see you here

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