Well, Gargoyle, you really need to have the piece under your belt to appreciate the humour. The background is that Anton Diabelli, a music publisher and (very) amateur composer, produced a little waltz tune (which Beethoven called "a cobbler's patch") and invited the major composers of the day to each contribute one variation on the waltz. Beethoven might have been a bit sneery about the tune, but he saw the potential and eventually produced not one but 33 variations, which take the best part of an hour to play. He didn't produce them all in one go either. I have three versions, the first recording by Stephen Bishop-Kovacevich, one by William Kinderman and one by Andreas Staier, the latter on fortepiano. My favourite is the Staier, not just because it's superbly characterful but also because the CD also has many of the other composers' attempts (they don't look great alongside the Beethoven!). When I bought the Kinderman version it came with a little book that tells you all you need to know about the music, including how Beethoven, in several of the variations, was taking the mickey out of Diabelli's rather mundane waltz, but still the affection is there in spades...