I believe that the truth lies somewhere in between. JF you know your guitar but I have to disagree with most of your examples. Steely dan have been using so many fantastic guitar players and dumping so many of their contributions. MK's solo is clear and it is at the very least MKish. Steely dan was his first "hired job" so they treated his contribution very nice, in my opinion, given that he was not the guitar hero everyone wants in his recording with the signature sound.Yet the solo sounds definitely MK. But of course Larry Carlton has proven in previous Steely dan records that he can sound even like MK!
John Fogerty's song is basically based upon a riff very close to SOS, and I believe that either MK came up with the idea, or Fogerty after writing it saw the resemblance and asked the master to contribute-thus getting instant absolution!
I would agree about Mavis Staples, which must have been a coincidence or a helping hand for Wexler, the disco craze didn't help things either, but you can at least suspect that what you hear is MK. And on Illsley's recordings, it is more or less the same.
On most of his contributions you know it is him, even if what he plays is common and easy to imitate.
Private dancer is Dire straits without MK and even though Jeff Beck is doing a heck of a job, he doesn't sound like MK!
I think that the Sting contribution is the weakest one (3 guitar players listed, MK, EC amongst them), but what you hear is something with no breath, very confined.And then you have the Dandy warhols song, that he plays mandolin?! But I believe that most of them asked him for the unique experience to record with a talented legend and of course have a record that includes MK in the credits. I believe that this means a few thousand sales more.
And that is what he miss in his last 2-3 records. The distinctive guitar sound. And the few memorable and distinctive licks are not enough.
