In the beginning when I first started feeling the back of the U it was just a tiny horizontal line up nears the back of the ribs that would sometimes feel a tiny pulling down when I would do bending. Then one day after I had been doing UCB for maybe a year I all of a sudden felt the back of the U separate like it was three sheets of something and that had been glued together and then glue finally came apart and now it was a longer sheet of stuff. Today when I was doing the standning I was feeling the foot couple and transverse couple more clearly than I had been feeling it lately, and the back of the U had this slight upward supporting feeling like it was the upward part in a tensegrity object.
I know that you've said that in the pearls couple there is the pulling down in the neck ring and a slight upward pressure somewhere in the back of the neck of base of the head, so not sure if this is related or just different and if it is a feeling that will be consistent or just another thing that is changing over time.
