In response to some earlier comments about collaboration: I think that probably MK's playing on many collaborations is understated because he doesn't want to outshine or take center stage on someone else's project. He is basically a courteous, thoughtful, and professional musician. As a guest, his job is to complement the musician's project, not to call attention to himself. (Though for MK fans, his contribution is obvious and much appreciated.) Whether the part is overdubbed or they are in the same studio, it's still the primary artist's call, and MK is respectful of that. It's not talent or desire, it's professionalism.
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