The Beatles recordings that had the drums panned hard left or right were the result of American record company executives mistakenly re-mastering some tracks from the 4 track masters around the early '70 s for the 'Red' (The Beatles 1962-66) and the 'Blue' (The Beatles: 1967-70) double albums (which functioned as Greatest Hits in a way). George Martin wasn't involved in the project and was aghast at hearing the tracks.
As for the idea that Ringo didn't play on some tracks, as any of Lewisohn's books, and a basic awareness of multitracking, will show, this is a myth. All of the White Album tracks (including 'Sgt. Peppers') were recorded on a four track machines (sometimes linking two machines together). Because there were often multiple instruments, parts had to be recorded 'sound on sound', i.e., three of the four tracks would be recorded, and then combined by being bounced to the fourth track, 'locking in' all of the previous parts.
Because the rhythm tracks (incl. Ringo's drums) were put down first, it was impossible to re-add the basic drum parts later, so it's impossible for Ringo to not have been on these tracks. That accusation was made by a really famous session drummer in 'The Big Beat', Max Weinberg's book of interviews with 14 or so really famous and great drummers (including Ringo).
Just a little info.
I really like Ringo's snare sound, particularly on The White Album, and on the 'Please Please Me' album. Greenday's snare sound is very similar to this, on 'Good Riddance (The Time of Your Life)'. I always aim to make that my 'standard'/reference snare sound.
GVDV