YOU’VE PROBABLY ALL HEARD the phrase “Jumping the shark” by now. It’s a show business thing from decades ago that I think has been culture-wide for quite some time. (I only heard it myself about a year ago, which, considering I’m in show business, is probably pathetic.) In case you haven’t . . .

Fonzie was surfing (Now, how often do you get a chance to say that?) in an episode of Happy Days, and, well, he jumped a shark. I didn’t see the thing, but I think that’s close enough. Somehow it got around and became a catch-phrase among writer-producers as the point in the tenure of a show–comedy or drama–where it’s been on the air so long that some of the stories start to get a tiny bit preposterous. Then usage of the phrase spread to include various agents and executives who had also, just possibly, outlived their usefulness. Since most of them never had any usefulness to begin with, this was never big news, anyway.