[...] he loved pure rock and roll [...] or, at least, that's the image lots of people had of him ... even maybe him ...
I was thinking of that period of time too, Kevin ... he said later that he wanted to leave the band by mid 60s ... could be the real reason that he was embarrased of some of those songs you've mentioned? ...
John may be considered the 'pure rock n' roller' but it shows through the songs in The Beatles and after that Paul rocked more than John. Sure Paul had more sappier songs, but he still had more rock n' roll songs than John. John once complained that GM spent more time on Paul's songs but thats because Paul was with him pushing him to perfect his songs. Funny how no one mentioned that to John. To me it sounds like John was always complaining in his music and in real life.
You can read: "Paul holding a sheet of manuscript paper on which he had written the lyrics for the title track of "Sgt. Pepper"."
You can read: "As usual, Paul had lots of arrangement ideas for the songs he had written for the "Sgt. Pepper" LP. Here he is with George Martin, discussing the parts the French horns would add to the title track."
... and Sgt. Pepper's Lonely Heatrs Club Band (song) could be defines as rock, I think ...