John Cleese!
Still one of my favorite solo Paul McCartney songs. As far as the Linda co-credit, I think Paul was on a thing where he shared credits with Linda the same way Paul and John always shared credits in The Beatles regardless of who actually wrote the song and how much. She was his wife, and he's Paul Freakin' McCartney. People always asked him, and her, why she was in Wings. She shook a tambourine and played a few keyboard lines (with little stickers on the keys to show her which notes to play), and she sang background vocals but they turned her mike way down. But she was up there on stage because Paul wanted his wife up there with him. It's his band, so she's in the band. Simple as that.
Paul is one of those composers who constantly has 100 melodies and bits of songs floating around in his head, and once in a while he ends up stringing them together into something. A lot of his songs are like that; clearly made up of different things but put together anyway. I like it. It makes those songs like a mini-suite or something, with each of the bits a separate movement.