But those who know him understand precisely why he did it. It was a last, ill-judged bid to set right the one great failure of his eight years as General Director at Covent Garden: to make the Opera House beloved of the people. He wanted popular sentiment to swell with pride at this national treasure. Instead, those who presume to speak for the masses - the tabloids and the Terry Dickses - continue to heap contumely upon it.
He thought people should see the desperate backstage struggle to get shows on - and we do. Behind the plush, the place looks like the boiler room of a 50-year-old banana boat. Indeed, the drama of finding an unknown Carmen within hours of a crucial first night as the diva falls sick does convey the terror and the thrill of the whole bizarre enterprise.
But if Isaacs imagined this film would inspire admiration for a noble endeavour stretched to breaking point on a subsidy half that of the world's other great opera houses, he should have known better. The character who will be remembered is not the fragile little French Carmen, but the monstrous new public affairs director, who sacks everyone in sight and looks like an angry android in a Paul Smith suit.
This week Isaacs bumped into John Birt and Sir Christopher Bland dining in a restaurant. Birt asked him why he didn't like the film. Between gritted teeth, Isaacs parroted a well-known Birtism: "Because it suffers from a bias against understanding."
The trouble with fly-on-the-wall television is that incident always wins out over analysis. Part of the film focuses on rows over directors and designers overspending their budgets. In unguarded moments, Isaacs and his team display an apparently cavalier attitude towards money. Crisis follows the near-catastrophic hiring of one designer to do a huge new ballet at the same time as a new opera. A great deal of shouting in the boardroom ensues.
Aggrieved, Isaacs feels viewers might understand a little more and condemn a little less if there had been more emphasis on the financial facts: both productions mademoney back. For the past three years the Opera House has broken even, and the pounds 3.6m deficit Isaacs inherited has been reduced to pounds 500,000.
When Isaacs leaves his post next year at 65, he bequeaths his successor an energised enterprise with a reputation for innovation and daring. An outfit once stale and mediocre, down on its artistic beam ends, was shambling its way through 20-year-old Bohemes and Toscas in tired routines. The English National Opera and the regional companies were the happening places, while the Opera House reeked of mothball-scented furs. Now the ENO is in artistic trouble - short of ideas, enveloped in dark critical clouds. True, Isaacs has presided over some spectacular turkeys - but only a few, no more than the flip side of bravery.
He wanted to make opera accessible. When he introduced surtitles - simultaneous translations projected above the stage - the stuffed shirts complained of the vulgarity. Nowadays the only complaints come from those in seats where they can't see them properly. He curses the Sun and all those who patronise "ordinary" people by assuming them to be cloth-eared philistines. Don't they all know "Toreador" from Carmen, "Nessun Dorma", Mozart, Verdi, Puccini and a dozen other favourites? Hasn't the success of the three tenors shown how many "ordinary" people love opera, given the chance? He is proud of the work the opera house has done in schools. A natural romantic, he speaks lyrically of opera's transforming power.
All very well, but just how accessible can you be when you are touching people for pounds 260 for top tickets? He is ashamed at charging some of the world's highest prices. Two or three performances a year broadcast on big screens to a packed Covent Garden piazza make only a minor dent in the elitist nature of the business.
This makes him edgy and uneasy. From a Labour-voting middle-class Hillhead family, he is the son of a GP mother and jeweller father - and a man of the left, somewhat left of New Labour. He is not even slightly seduced by the ritzy, glitzy world of the royal box.
He made his name in 1974 with The World At War, a 26-part blockbuster history of the Second World War, which reached audiences of 15 million. As the first head of Channel 4 in 1980, he opened up the institutionalised world of television to outsiders, new groups, experimenters and some lunatics. The result was a remarkable injection of energy. By helping to devise a system where the funding came from ITV, irrespective of ratings, it gave him the freedom to allow some outrageous things to flourish.
So his move to the most establishment post in the arts world came as a shock. Why should this naturally rebellious man choose frock-coated opera? Because he is driven to spread his own passion for opera and ballet to a wider public. Alas, it has been a mission thwarted by an impossible dilemma: he spends millions of tax-payers' hard-earned money, yet not millions enough to let in most ordinary tax-payers at prices they can afford. Those who come after him may fare better, for everyone expects the Lottery funding rules to change to allow money not just for buildings but to fund productions and cheap seats.
What will this television documentary do for Isaacs's reputation? No justice, say his friends, defensively. It doesn't help that he looks like a rumpled, slightly-the- worse-for-wear Beethoven. Or that he always says what he thinks, straight out. The scenes of apparent chaos and in-fighting tell only part of the story. "What artistic enterprise would ever get on to the stage in an atmosphere of total calm, harmony and managerial efficiency?" wonders one seasoned observer.
Isaacs's most passionate supporters are those who have worked for him, both when he was head of Channel 4 and at the Opera House. His detractors are among the boards and governors he has worked for, which is, on the whole, the best way round: "He lacks some essential political skills for a job like this," says one. But another, who worked under him at Channel 4 retaliates: "A complete hero!"Reuse content