Highly unusual.
My Mistake. There are 12 tracks, four of them were recorded before the musical opened, but it's not relevant, because, although the music appears on the CD, it was not part of the musical. They went into the studio to record 'Fiddler' the month after it opened. Which is still sort of soon.
Fiddler opened Sept 22, 1964. Cannonball went into the studio to record on Oct 19, 1964.
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