Few comedy writers can bring themselves to quit while they're ahead. And most comedy series keep chugging along, running on empty before they peter out with a phut. Fawlty Towers is an exception - each episode is a jewel. Perhaps they ran out of money - constraints, even financial, can be liberating for comedy.
Roseanne was funny once - hard to believe, I know. So was Friends, yet how feeble towards the end, when all the men got too fat and the girls too thin, and everyone had slept with everyone else a dozen times. Sacha Baron Cohen was so funny in Borat it is hard to believe he come up with such a limp sequel. And Curb Your Enthusiasm was so original and so quirky, who could imagine that it could go the way of the others? But it did. And the kiss of death? Celebrities. Just one "guest appearance" by a celebrity ruins a show. Larry David took this further and had the whole cast of Seinfeld, the show he wrote.
Last Thursday's episode of Curb had Larry David sitting on a sofa laughing at Seinfeld. Did he later sit on his real-life sofa laughing at himself sitting on a sofa laughing at Seinfeld? Between trips to the mirror?
Larry David, of all people, who could see the funny side of ordinary things, and the dangers of the ego, should have known better. Shame - damn good show in its day, and a cracking title.