Analysis of information sources in references of the Wikipedia article "Thirty-two-bar form" in English language version.
{{cite journal}}: CS1 maint: multiple names: authors list (link)In a nutshell, the format of the performance of a jazz tune is: head for one chorus - improvised solos for several choruses - head for one chorus.
Verses were regarded as mere introductions by the 1920s, and today the verses of Tin Pan Alley songs are infrequently performed.
Although the Tin Pan Alley song-type continued to include verses, these most often were much shorter, sometimes serving as little more than introductions. The song became, in most cases and for most purposes, coextensive with the chorus. And, as was quickly learned within the time-restrictive environment of recording in the 1920s, the new Tin Pan Alley song, uprooted from the stage, worked best without its verses, as a fragment of expression that was somewhat fluid.