There are some odd judgments and infelicitous editing choices, but overall Sagolla's bio is a good one. She's stronger on the dance world than on Broadway or Hollywood, but she makes an honorable effort to address all aspects of McCracken's career.
Sadly, Ray McDonald, who is the male lead dancing opposite Joan McCracken, also died quite young. For unknown reasons, he never quite established himself at M-G-M and this would be his last film at the studio. (Maybe his looks weren't quite leading man handsome?)
Could be. And/or maybe they just didn't see a need or niche for another dancing man.
He did a wonderful softshoe to "By the LIght of the Silvery Moon" in Babes on Broadway.
Thanks for the heads-up -- I remember the number a bit, but will look more closely the next time I watch the film.