Chapter 16: I reattached the clutch disc and pressure plate to the flywheel, and the fork and throw-out bearing to the bell housing. Then I tested the clutch by attaching and moving a long lever arm on the end of the fork. The clutch disc spins easily when I simulate pressing the clutch pedal! From this I can only conclude there is nothing wrong with the clutch.
The only explanation I can think of is binding between the pilot bearing and the transmission shaft. I will replace the pilot bearing and re-install the engine to see what happens. I guess I shouldn't be surprised. Under a different post on this site (search under "pilot bearing"), I explained that I had to beat the tar out of a new pilot bearing to force it into the engine. Maybe I damaged the bearing even though it visually looks fine. Stay tuned.