11.   Older footage predominates -- Gypsy Rose Lee explaining what a fan dancer does, Amelia Earhart with her plane -- because it is in the public domain.

12.   Some professional dancers do it to maintain flexibility and stay fit without adding excess stress to their bodies.

13.   The other dancers occasionally do a stylized soft shoe and wiggle their behinds.

14.   What the dancers could do, clearly, is balance on the palm of a hand and the sole of a foot.

15.   When they are singing, they flesh out the moving, acting body in a way that a dancer cannot do.