In the broadcast media, technical considerations can often shape events, and sometimes create them.

To illustrate this awkward truth, let me begin with a quotation.

“It was said that I was facing political oblivion, my career in tatters, apparently never to be part of political life again. Well, they underestimated Hartlepool and they underestimated me, because I am a fighter and not a quitter.”

When Peter Mandelson made this brief, improvised and personally damaging speech in Hartlepool in 2001, all those watching him on TV, including the prime minister, Tony Blair, thought it must mean the end of Mandelson’s career. He sounded shrill and petulant. When he saw himself on screen later, he would have agreed that his performance was of an unsettling stridency. I myself, after a working lifetime in television, didn’t guess immediately what had really damaged him.

It was the sound balance. The audience at the announcement had been very noisy. Mandelson had been shouting against the noise. The microphones on the podium were all pointed his way, so they had left the audience out. The next night, after seeing the moment replayed a few times, I belatedly figured out what had happened, and sympathised with the victim. It had happened hundreds of times to me, with a cumulatively disheartening effect that finally got to the point where I trusted studio production no longer.

For years I had been knocking myself out in studios with an invited audience, only to view the show and hear no convincing evidence that the audience had been present. On the night, their reaction had been a tide of friendly enthusiasm that I had to raise my voice against if I was to keep the momentum. In the transmission, I was just a man raising his voice. On countless occasions I protested to my own producers. All repeated the sound engineer’s opinion that the audience’s reaction had been faithfully captured, and the optimum balance between performer and audience had been attained. In other words, accept the professional opinion of the technicians, or else get out of the studio altogether.

Eventually I chose the second course, and one of the reasons — there were several, but this was the one that had been nagging longest — was that the problem of performing on two levels had proved insuperable. To entertain the audience in the studio, the performer must project, as on a stage. To entertain the audience at home, projecting is the last thing a TV performer should do. All the evidence of my time in British studios suggested there was no remedy. The evidence presented by US television we had better leave aside, except to say that the reason their discussion programmes are so often better is that they know how to favour the talking heads and forget about tarting up the design. Too many British on-screen personnel sit alone at some design masterpiece of a desk in the middle of a set the size of an aircraft hangar. In the US, the set is rarely much bigger than the number of people it contains. Their talk shows are rowdy, scruffy events, but one thing you can never complain of is a sense of the performer slaving away on his own. The audience is at least as amplified as he is. Plus there are always plenty of shots of the audience to prove there are real people there.

I could rarely persuade the directors on my shows to include shots of the audience, perhaps because the directors didn’t much care for the adverse sartorial effect that might be created by old ladies wearing knitted hats who had to be brought in by bus. British TV directors all want to be film directors one day, and they care about the look of the thing. As a result of this misplaced visual fastidiousness, I regularly had to read newspaper reviews in which it was stated that I had been mugging away to an empty studio. This opinion was usually given by some young wit who would have been able to swear in a libel court that the evidence of his eyes and ears led him to no other conclusion.

After a few decades of that, I had plenty of experience behind me in order to assess how Peter Mandelson must have felt when he saw himself on screen and realised that he had caught himself out. But I still didn’t spot it while it was happening. That’s how tricky a game television can be. Unless you can lay down conditions in which you can both be performing and watching yourself perform, you will eventually be caught looking like a dunce, and usually at the moment when it matters most.

Peter Mandelson survived his bad moment, and indeed all his other bad moments. He cried all the way to the House of Lords. But neither he nor anybody else will ever forget the night when the sound balance made him look childish. A politician can stay upright even after being savaged in Alastair Campbell’s diary, but the wrong few minutes on screen can rarely be expunged. There could be no clearer instance of how TV, at least in Britain, has become a city of nets. In America the politicians are better protected, by a team of people with no other task except to ward off danger from technical errors. Sarah Palin walked the plank on air, but at least the fault was all hers.

The Revolt of the Pendulum: Essays 2005-2008 by Clive James is published by Picador next month, price £15.99. It is available at the BooksFirst price of £14.39, including p&p. Tel: 0845 271 2135

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