An item on Radio 4's Today yesterday told us that it was 40 years since The Frost Report first aired. On The Frost Report is Back! (BBC Four), Sir David himself contradictorily announced that it was 40 years since the programme won the Golden Rose of Montreux. (The hideous item eventually appeared on his desk, although Frost did not entrust it to his perceptibly shaking hands.) In fact, the last Frost Report was broadcast in December 1967. In other words, 2008 is an anniversary of nothing. Frost's production company made this love fest to himself last year and the BBC has been sitting on it for, I would guess, 11 months. Thus does the corporation, normally so keen on an anniversary, treat its once favourite son.

Perhaps someone noticed that if The Frost Report was, as it claimed, “back”, it had declined into a 90-minute chat and clip show. The only new material was a divvied-up monologue of political slang “21 Century Style” (as Frosty unusually phrased it). In a reversal of the American chat show model in which the MC is supported by a less-talented straight man, to help Frost through the ordeal was Ronnie Corbett.

The gang all turned up - apart from the producer James Gilbert, who would have loved to, but couldn't, and the late Ronnie Barker who was represented by an empty chair. Folk singer Julie Felix had not changed her hairdo in 40 years and cantered through Blowing in the Wind. The writer David Nobbs explained that dumbing down had not been heard of back then. Long “working” lunches had been. Denis Norden recalled Keith Waterhouse and Willis Hall introducing him to the useful phrase: “Well, it's hardly worth going back to the office now.”

Sheila Staefel, the statutory woman cast member, appeared, looking 20 years younger than her 72 years. “Sheila at her very best as ever,” said Frost (as Norden said, it was all about the love of language) hailing a sketch in which she played Barker's wife. It had Barker trying to wrangle from her whether or not she wished to go out. Frustrated, he went into the hall and shot himself. It was by far the funniest item in the show and proved Sir Antony Jay's point that the programme retained its relevance because it satirised not politics but society, which changes more slowly than we think.

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That said, another Staefel sketch from Frost Over England demonstrated that society does change. Here Barker, conked out in a dentist's chair, fantasised about chasing the dental assistant (Staefel) around a park and raping her. The punchline was that he woke up and really had.

Tim Brooke-Taylor explained that The Frost Report was a reaction against the satire of That Was The Week That Was. Its aim was silliness. The writers were thus allowed to be an eclectic bunch (i.e. some had not been to Cambridge). The cross-fertilisation worked. The Goodies, Monty Python, The Two Ronnies, Marty (Marty Feldman's show) and Yes, Minister were all made by members of Frost's team. Yet as we watched the brilliantly performed, if not now very amusing sketches, a question shuffled uneasily in the wings: what did Frost actually contribute? There seemed animosity towards him still. John Cleese even did a cruel, whiny impression to his face.

It was left to Antony Jay to speak up for the boss. David, he said, was a great finder of talent, a good judge of scripts and an expert at motivating people. But in nailing the myth that this programme was ever satirical, the belated celebration identified a trig point in the decline of Frost from the force he might have been to what he became. The Frost Report was when Frost began to go soft.

Parents this cold Easter will have been thankful for Terry Pratchett's The Colour of Magic (Sky One). The two-parter was better than Sky's previous Discworld adaptation, the story more clearly told (I could understand it) and David Jason happier as the hopeless wizard Rincewind than as Albert in The Hogfather. It also benefited from an excellent villain in Tim Curry. It looked good, in an over-glossy, Hallmark Productions kind of way, although every now and again the budget (tight, it was implied, by the accompanying “Making of” documentary) looked stretched. If it could show characters falling off the edge of the world, make a trunk walk and blow up the Broken Drum Inn, why is it impossible for the skeleton Death to open its mouth when it speaks?

OUT OF THE BOX

Much excitement, if short lived, when I discovered a new website, hulu.com, that allows you to watch clips from episodes of current and classic US TV programmes. It works like YouTube in that there is no software to download and nothing to pay. It is paid for by advertising and the list of available content is expected to expand soon to include even the latest episodes of Lost. The disappointment? The site does not let you see anything if you are logging on from the UK. Let's see how long it takes someone to crack that little problem.

Sheila Staefel, in fine form on The Frost Report is Back!, was also Mrs Harry H.Corbett. Last week she was portrayed by Zoë Tapper in that excellent tragedy, The Curse of Steptoe. Good to see it earned BBC Four its highest-ever audience: 1.4 million on Wednesday.

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