I got to thinking...the clutch chatter on my Vanagon seems to happen
mostly when I haven't driven it for a while.  After a while it goes
away.  (Bear in mind this is not exactly a daily driver vehicle -- it
sits a lot.)  Now, my brakes are grabby too under those conditions, and
I realized after a while this was because the rotors were developing
surface rust while they sat, which I was scrubbing off with the first
few stops.  Could the same thing be happening with my flywheel?