In a magnificent jeremiad last October, Tony Robinson tore into an audience of media grandees. Public service broadcasting was on its knees, he cried. "We've lost those bits of television that are difficult to make. The whole culture of risk-taking which has driven every new step forward in British television is now almost a dead duck."
You are not meant to talk that way in broadcasting, and Mark Thompson, the director-general of the BBC, quickly restored order. The BBC, ITV and Channel 4 were a "family" of public service broadcasters, he told the meeting, dedicated to the noble mission of giving the audience what it needs to know.
A glance at Robinson's own genre of factual programmes shows why the old actor was right and the director-general years behind the times. Britain has developed three styles of documentary making. At first, channel controllers allowed acknowledged authorities - Kenneth Clark, David Attenborough - to use the tricks of television to educate the public. You can still see the old style in Simon Schama's and Niall Ferguson's documentaries, although, tellingly, modern producers now require their experts to jump about like twitchy teenagers and gibber like Oprah. The second wave saw producers bring in Robinson, Michael Palin and other celebrities to front their shows. The star vehicles were not always crass. Robinson's Time Team, for example, is a thoughtful series that persuasively conveys the work of archaeologists to a wider public.
The third and latest style is narcissist television, about which I can find nothing good to say. The documentary presenter is neither a celebrity, who might be expensive, nor an authority, who might be boring, but an egomaniac: one of the worrying new breed of journalists who report on their emotions and, by extension, the emotions of the self-obsessed viewers at home. If Mark Thompson wants to understand why he has no right to be complacent, he should take a long, cool look at the work of Bruce Parry.