It's well known that The Beatles made good use of every existing musical idiom in their work, a side-effect of talent borne from constant live performance. In this case, I'm curious if anyone can help me identify a musical precursor to one of their idiosyncrasies.
One unusual feature is an extra beat in the tune "Don't Let Me Down" that breaks the prevailing 4/4 signature in a lead-up to the chorus.
The five beat bar precedes the word "does" in the chorus line "like she does."
( )"Nobody ever loved me like she does..."
( )"And if somebody loved me like she does..."
Is this five-beat-bar in a 4/4 song a Beatles innovation? My inclination is to doubt it, and I'm curious if there are examples of popular music earlier than this tune that use a similar extended bar that the Beatles may have borrowed this style from.