Judging by a spate of recent appointments by major opera houses, you’d be forgiven for concluding that the best qualification for directing an opera is having no qualification at all. “I have no idea what I’m doing,” Woody Allen gamely told reporters, having accepted an invitation to direct Puccini’s Gianni Schicchi at the LA Opera next year. But, he added winningly, he’s never let incompetence stop him before.

And David Cronenberg said of the operatic version of his 1986 gothic horror flick The Fly that opens at the Paris Opéra in 2008: “As a director I can only mess it up. I’ve no experience at all.”

Most recently here, the film-maker Sally Potter exhaustively touted her lack of credentials in a raft of articles, interviews and video blogs ahead of her directorial debut with Carmen at the ENO last week. She thought opera “a dinosaur” of an art form. Little wonder the ENO’s artistic director, John Berry, hounded her for a year before she agreed to direct one.

Only, why did Berry hound her? Carmenwas met with a chorus of critical dismay. “I can’t remember when I last saw a Carmenso full of Spanish clichés,” Richard Morrison wrote in The Times. That Potter seemed to lack the most basic elements of stage-craft was a sentiment echoed all across the national newspapers.

“Opera is a completely different medium from film and theatre, and we forget that at our peril,” says Graham Vick, currently preparing a stadium-sized La traviata for Birmingham Opera Company. “If you don’t understand what a composer is trying to say musically, you’re not going to be able to express it. If you don’t understand the music, the opera won’t work. It’s that simple.”

On the phone from Athens, where he’s directing Verdi’s Simon Boccanegra for the Greek National Opera, David Alden is equally impassioned. “Give someone with no experience at all a main house opera to direct you have only a 20 per cent chance that it’ll have any lasting value,” he says. “And when you’re talking in the sums of money you have to with an opera” – somewhere in the region of half a million pounds a pop – “that’s decadent decision-making. It’s ludicrous.”

Perhaps it’s Anthony Minghella’s operatic debut with Madam Butterfly at ENO that illuminates most clearly why opera houses would take such vast and public risks on first-time directors. Minghella’s commission brought New York to a standstill last autumn, when it transferred to the Met. It was stunningly successful at drawing new audiences to opera and gained more media attention than any other production in the past ten years.

But Vick’s concern is that, under the resulting influx of theatre and film directors, opera increasingly tries – and fails – to ape the naturalism of those genres. What he calls the “hands in pockets” school of directing, in which singers are asked to act first, and produce the sound however they can, necessarily manacles the music. “Opera is profoundly nonnaturalistic, and it shouldn’t have to apologise for itself. But what really pisses us off is that if enough of the other pieces of a production’s jigsaw are in place, audiences might not notice that only 30 per cent of the expressive power of the music is being released.” David Pountney, who first dazzled British opera in the Eighties at the ENO with a string of sensational, revolutionary productions, takes a more measured view. “It’d be very boring and protectionist to say that somebody who can’t play a Beethoven sonata has no business directing an opera. And it’s often refreshing to see somebody with no preconceptions tackle the big pieces, though it’s true to say that, most of the time, film directors especially make really pointless, pretty operas with lots of other people’s money.”

There’s no denying that cross-fertilisation and new audiences are vital to keep the genre on its toes. But it seems difficult to disagree that it’s a good idea to learn your craft before taking on an entirely new artistic discipline on the largest stages in the Western world.

Then again, as Pountney concludes, “it is perhaps worth remembering that you don’t have to be inexperienced to make bad operas. We’ve all done it.”

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