>>But I think the music John did with Yoko sort of disqualifies his opinion.<<
Wasn't it Paul McCartney who gave us rock gems such as Uncle Albert/Admiral Halsey, Silly Love Songs, Say Say Say, Coming Up, Smile Away, Mary Had a Little Lamb, Hi Hi Hi, Let 'Em In, With a Little Luck, ad nauseum?
So much for that argument.
Besides, the music Lennon made with Yoko was a small percentage of his total body of work which is clearly superior to brother Paul's.
McCartney's solo work and with Wings is so syrupy your turntable may think it's playing pancakes.