Why not? It's has become pretty clear that melody is what matters first and foremost to him. I personally don't think that all of his lyrics suck
- a lazy opinion that has become pretty popular over the years, but I sometimes do feel that more work put into the words could've improved some of his songs.
Just look at Elton John. Like Paul, he's got an incredible ear for melody and from what I've read, can knock one out even in his sleep. Yet, 'Tumbleweed Connection' and 'Madman Across The Water' (and probably others, I've only heard those 2) do benefit a lot from him having Bernie Taupin as a lyricist. The first's an unmatched Old West portrait and the second contains some of my favourite character-studies.
Another good example would be Brian Wilson's collaborations with Tony Asher (on 'Pet Sounds') and Van Dyke Parks (on 'Smile').
So, has Paul ever attempted anything like this before? (not really familiar with his post Tug of War work). If no, should he?