I think in earlier days MK had a strong focus on guitar playing which meant that he practised a lot and developing guitar parts/licks/melodies were a very prominent part of his songwriting. Somewhere in his solo career (probably during the STP period) I think he has lost that focus. It could very well be that this has something to do with him getting older, losing the souplesse in his fingers and avoiding struggling with it as a consequense. When it is gets to live performances I once read an interview with Hal Lindes and he said MK was constantly trying to improve upon the perfect solo's for the songs, which meant that he played for 90% the same notes on each subsequent night and experimenting in little parts to get it even better. Nowadays it's nothing like that, he's just improvising for the most part. This results in something far from perfect, even quite bad at times because both mind and fingers work at such slower pace. Also keeping the same songs in the setlist night after night and tour after tour does not help either, it would be a miracle to remain truly inspired. Just some thoughts...