Sure. But there are lots and lots of Beatles songs (for example) that shift keys in the main verse, often very early in the song (and often several times). Key

Sure. But there are lots and lots of Beatles songs (for example) that shift keys in the main verse, often very early in the song (and often several times). Key changes used to be something most bands handled easily, and the best songwriters got a lot of mileage out of it.