John's Stupidest Aggrandizement of Yoko

This is a tough one, because Yoko literally turned John Lennon into her
sycophant slave.  However, Lennon's implication that Ono authored
"Because" is up there.  Lennon famously said that he heard Yoko playing
Beethoven's "Moonlight Sonata."  He asked her to play it backwards, and
"Because" was born.
Bullshit!  Yoko couldn't have played that simple piece *forwards*  She
couldn't play the piano (or any instrument) at all.
George Martin once said that he would see quotes from Lennon interviews,
and that "I can only conclude that he was not in his right mind" he
uttered them.  I'd bet that the quote about "Because" is one such
occasion.