George's guitarwork on What Goes On is some light country chicken'-pickin', fitting because it is basically a country song. No joke, this one is in my Top Ten, I've never considered it one of their knock-offs. To me it's the quintessential group effort. Ringo takes the lead vocal and IMO he does it and the drums perfect, one of his most brilliant moments. I agree that the bass cooks, and George does his thing right on track as stated above. John and Paul do some intense back-up vocals that are as authentic as any bona-fide open-throated bluegrass harmonizers.
The whole song is performed so dynamically and tight. The Beatles recorded it in 1 or 2 takes and never played it again. Too bad. Even when doing a country song, to me they did it better than the Nashville regulars--like the Lovin' Spoonful did on Nashville Cats, another great one. Of course, the Beatles earliest roots were in skiffle, and that was not that far removed from country. This would be one I'd still like to hear Ringo and Paul do together. Call me a nut, but time still stands still when I play it, I love it.