Funny how some drummers slip through the net. Not listed on the DW page, no one's included him here either.
I think it's because he's mainly just known for playing on King Crimson's Islands
. He's better than those recordings suggest and he was by no means limited to prog, and he's a top echelon player. Some artists he's played for:
Crosby, Stills and Nash
The Traveling Wilburys
Not sure how many have heard his jazz playing ... here he is playing a cover of 21st Century Schizoid Man
with the Crimson Jazz Trio: http://www.youtube.com/watch?v=mE6Ptqw3DYc