total convenience and flowers seven days milk:

It's also indicative of a change in popular entertainment patterns--at one time, *everybody* knew at least basic partner dancing, and dancing was not only a central courtship ritual but an important part of socializing among married couples. So if there somehow were an equivalent of Dancing With the Stars in, say, 1930, being able to not only perform but lead common social dances was an expected part of being an adolescent or adult male.