I have had a couple of involuntary downgrades in the last year.

One, was to a Volkswagen Rabbit (compact) which was probably a lot nicer than whatever they would have been offering as an intermediate, which I had reserved. They had adjusted the price downwards for the dollar or two a day for the compact vs. intermediate cost. That wasn't so bad.

I _always_ print out and carry my ininerary with me. On another occasion, I was involuntarily downgraded to a compact and they tried to tell me "that's what you reserved, sir..." With proof in hand, I ended up with a decent upgrade.

Usually stations pull this s**t when they have run out of cars.