Mania, Indeed

Apparently there's a cottage industry devoted to convincing people that The Beatles were not four people, but a machine of hundreds:

It’s true that the Beatles maintained a rapacious schedule of touring and recording. Their discography shows a staggering 27 studio albums released in a period of 8 years. Granted, these weren’t 27 separate album sessions—these songs were often recycled into different packages for different countries. But even today, that’s remarkable output. I think even Gucci Mane would admire it. 

So could it be that the Beatles—meaning the amalgam of managers, record executives, producers, engineers and the Multiple Beatles—required body doubles? It would sure help with hellish schedules—not to mention safety.