What is so special about You Were Never Lovelier?
It's a pretty standard romantic comedy. Two unlikely individuals meet one another, develop an instant and strong distaste for one another, then spend the rest of the film falling in love. There are a few unique twists here, but that's the basic formula.
This formula can be repetitive and dreadful to watch (see 99.9% of all RomComs from the past few decades). Done right, though, as it often was in the 30s-40s, there might not be a genre of film that delights me more.
The specific pleasures of this film rely on the two lead performances; Astaire's irresistible charm and nervous joy and Hayworth's volatile synthesis of gentle domesticity and "predatory" femininity. Both of these wonderful actors perfectly capture, encapsulate in an abstracted genre microcosm, the dizzying process of courtship.
What about the music?
What is remarkable about the music is that it is all entirely organic to the story. For the first half of the film, we get orchestras and singing and dancing because Hayworth's father (played with a perfect balance of seriousness and farce by Adolphe Menjou) owns a nightclub. The first time that the use of music strains the boundaries of the credibly real is when Astaire and Hayworth begin to fall in love. As the courtship continues, this happens more and more, with the couple's communication occurring primarily through song.
This is glorified speech, reflecting the glory of two souls coming together. Not only does the singing reflect this union aurally, but there is also a strong visual metaphor of hearts uniting when the two can dance together without practicing or talking things through first. What I had once dismissed as ridiculously unreal actually becomes the chief means of portraying truths in the most gracious and economical way possible.
I'm still not a fan of the big musicals that hold a primary place in pop culture (Mary Poppins, Sound of Music, Fiddler on the Roof, etc.), but You Were Never Lovelier totally surprised me, knocked down my defenses, and allowed me to see clearly for the first time what at least one aspect and expression of The Musical can be at its best.