Never heard about the Disney monorail, but the demise of the PE is a subject that will open a can of worms. There are dozens of books, some rabidly claiming it was a dastardly conspiracy of GM, Standard Oil and Firestone (or some such combination of companies), others that poor service, the old equipment, and a poor safety record sealed its fate. Seems to me that people just wanted to drive their own cars, and why wouldn't they? The new systems are great, but only if you live and work near the lines.