In the latest installment of What Might Have Been, Paul McCartney disclosed that the Beatles occasionally discussed the idea of reuniting. Unfortunately, talks never got past the preliminary stage due to what McCartney called a lack of "passion behind the idea" and fears over whether their newer work together could approach the standards set by their brilliant catalog.

"[I]t could have spoiled the whole idea of the Beatles, so wrong that they'd be like 'Oh, my God, they weren't any good,'" he told Rolling Stone. "The re-formation suggestions were never convincing enough. They were kind of nice when they happened – 'That would be good, yeah' – but then one of us would always not fancy it. And that was enough, because we were the ultimate democracy."

Despite the bitterness of their breakup, the Beatles have often appeared on each other's solo recordings over the years. Their only reunion under their group name came in 1995 when they recorded overdubs onto a pair of unreleased John Lennon demos for the 'Anthology' project.

In October 2010, McCartney surprised Ringo Starr at his 70th birthday concert at Radio City Music Hall. There was also the famous story about how McCartney and Lennon nearly took 'Saturday Night Live' producer Lorne Michaels up on his offer for them to reunite for the show.

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