By now, the phrase "jump the shark" is a piece of cultural shorthand, an easy way to pinpoint the exact moment a beloved institution began to overstay its welcome. The phrase refers to a much-lamented Happy Days episode in which a vacationing Arthur Fonzarelli has to water-ski over a shark. Now the WGA-credited writer of that episode, Fred Fox Jr., is stepping up to defend it, arguing in an op-ed that this was not the beginning of the end for the series. That's right: Happy Days didn't jump the shark when Fonzie jumped the shark. Explains a good-natured Fox in The Los Angeles Times:

I still don't believe that the series "jumped the shark" when Fonzie jumped the shark.

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Now, whose idea was it for Fonzie to jump the shark? Amazingly, I can't remember — which is frustrating, as I can usually watch a "Happy Days" episode from any season, hear a joke and recall who wrote it. My friend Brian Levant, then a talented new member of the writing staff, believes that Garry Marshall, the show's co-creator and executive producer, and Bob Brunner, the show runner at the time, made the suggestion. But what I definitely remember is that no one protested vehemently; not one of us said, "Fonzie, jump a shark? Are you out of your mind?"

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Was the "Hollywood 3" episode of "Happy Days" deserving of its fate?

No, it wasn't. All successful shows eventually start to decline, but this was not "Happy Days'" time. Consider: It was the 91st episode and the fifth season. If this was really the beginning of a downward spiral, why did the show stay on the air for six more seasons and shoot an additional 164 episodes? Why did we rank among the Top 25 in five of those six seasons?