Philip Hensher: Alesha for Arlene is pure dumbing down

Earlier this year, the BBC stirred up a fair amount of irritation with the news that it had sacked one of the judges of its popular Saturday night celebrity talent show, Strictly Come Dancing. The BBC was looking to refresh the line-up of judges. Arlene Phillips, though a very experienced choreographer, was felt by the BBC to be the main candidate for removal.

When the news broke that she was being replaced by Alesha Dixon, whose qualifications for the role seemed to be that she had once won the competition and was several decades younger than Phillips, scepticism was nearly unbounded. Strictly, as its aficionados call it, is not like The X Factor, say, or other talent competitions. Other competitions thrive on critical comments limited to: "You really made that song your own," or "That was the worst performance I've ever heard." Strictly is enjoyable and interesting because the judges know what they are talking about, and their comments are soundly based, well-informed and detailed about shoulder positions and footwork. Could Miss Dixon be as accurate?

Two shows in, and the audience is up in arms. Miss Dixon's comments were generalized – "You always bring the spirit to the dance" – or bizarre – "He's wearing pink". She had to ask the audience to tell her who the most entertaining dancer of the night had been. She gave the impression of giving her one piece of technical advice to more than one dancer, telling Jade Johnson and Martina Hingis that there arms were "a bit fly-away".

Reports from the studio suggested that she may have asked her fellow judge Bruno Tonioli, and, weirdly, her mum and grandmother in the audience to suggest an opinion. Len Goodman, the chair of the judges and a knowledgeable man, tried to defend her against a tidal wave of online obloquy but ended up saying "She has limited knowledge on technique."

I don't blame Miss Dixon, who is being paid £100,000 for this. I blame the BBC. For some years, the corporation has shied away from any kind of expertise in its arts programmes.

Classical music is introduced by that Charles Rosen of today, Mr Alan Titchmarsh, whose qualification for the task seems to be that he likes to listen to the "Serenade for Tenor, Horn and Strings".

In 2003, the corporation's Big Read project included a series of documentaries fronted by a strange mix of people: they were either genuinely knowledgeable about author and book, or they had been chosen only in order to lead us to literature with a vaguely familiar face – Jo Brand on Orwell, Alan Titchmarsh (again) on Rebecca, Ray Mears on Tolkien.

I'm not arguing for the professionalisation of all critical comment, but it seems self-evident to me that a BBC programme about dance, art, literature, or music will be most enlightening and interesting when it uses experts. Would they broadcast a football match with live commentary by Nigella Lawson?

There are a number of delusions at work behind Miss Dixon's appointment.

The first is that an audience will be unable to watch a programme without a sufficiency of friendly, pretty faces that they already know.

The second is a confusion between the notion of "constructive criticism" and "undiscriminating praise". Miss Dixon has clearly been brought in to be sweet to the worst contestants. The trouble is that her criticism is not constructive in the least; so far, she has hardly said a single thing which anyone could take away and use to improve themselves. Miss Dixon did well to win the competition, and she is an effective performer. So far, her presence and comments fall so far below the established level of Miss Phillips as to provide a single, undeniable instance of the BBC's dumbing down. A complete disaster.

Bluebottle cheats swatted

The Formula One driver Nelson Piquet Jr has said that he was ordered to crash his car deliberately during the Singapore Grand Prix, allowing his Renault team-mate Fernando Alonso to win the race.

The Renault team boss and the engineering head have left their posts. A disciplinary hearing takes place today against the team, which is said to have perpetrated the biggest cheat in sporting history. It's quite difficult to care. Formula One racing strikes me as the most desperately dull of spectator sports, comparable to watching 20 bluebottles in a jar – albeit millionaire bluebottles.

Whether there is anything more to it than spending vast amounts of money to belch a few more cubic metres of poisonous fumes into the atmosphere, I couldn't say. When huge sums of money are spent to display some implausibly advanced engineering and some sharp reflexes, the question of cheating seems somewhat beside the point.

The Piquet case might even disprove what had always seemed the main appeal of the sport. If the audience wasn't tuning in with the morbid hope that they might get to witness a violent crash or two, what on earth were they watching for? Really, the burning of $10m (£6m) on live television might prove more entertaining, and that would hardly allow for the possibility of cheating.

Wonderful score and set bring 'Le Big Mac' to life

Heavens, I enjoyed English National Opera's new production of Gyorgy Ligeti's Le Grand Macabre. It hasn't been staged in this country since 1982, and the team from the Catalan theatre group Fura dels Baus did this mad, scabrous festival of sex, shit and death proud.

It's Ligeti's transitional piece, beginning in a mood of Dada shrieks, clusters and dense clotted textures, and proceeds through collage techniques to a finale which seems to rediscover harmony, a place where a minor third sounds the freshest noise in the world.

The Catalans matched the wonderful score with a spectacular set; a revolving giant naked woman on all fours, from whose bottom or mouth the cast made their dramatic and unexpected entrances.

It was so ideally done and greeted with such enjoyment that you feel more people ought to be able to see it. Alas, it's only on, in the customary way of opera staging, for five more performances. As we all know, revivals of contemporary opera – even of a relatively established 30-year-old like Le Grand Macabre – are an unpredictable affair.

Still, I hear that the orchestra have taken to referring to the opera as "Le Big Mac", and that must indicate a degree of enthusiasm, even fondness, from a notoriously hard-to-impress bunch of musicians.