We both thought this was an interesting metaphor and was providing an intuitive visual message regarding what was happening during her treatment.
Also, the preferred acupuncture point to treat shoulder pain, such as a frozen shoulder, is "Spleen 6". This point is located in the lower legs. You can massage the acupuncture point located on the opposite side of your shoulder pain. For example, if you are having left shoulder pain, rub the acupuncture point known as Spleen 6, on the right leg (see photo example). Most likely, this point will be tender.