Last night my old boss, Charles Moore, was being interviewed about his new book at Policy Exchange, the think-tank that he used to chair. I worked for him when he wore a different hat, though, when he was editor of The Daily Telegraph and employed me first on the comment desk and then as obituaries editor.

It was, however, as a biographer that he was being questioned by George Osborne. Besides the novelty of seeing a journalist being interrogated (quite well, actually) by a politician, what was striking was the candour, and the clarity, with which lives can be examined after the subjects are safely dead.

I hesitate to bite the hand that once fed me, but I point out that, while his work has been greeted with universal plaudits, this is Mr Moore’s first shot at biography. And he’s only reached volume two. Whereas, thanks to him, I’ve written two or three thousand biographies, occasionally in less time than he took to chat to the Chancellor last night.

He’s had the luxury of time, of course. In 2003, he was already Mrs Thatcher’s official biographer, and retired as editor to devote more time to it. Ten years later, volume one appeared. Two and a half years on, we have Everything She Wants, a title shared with a hit by Wham! – something I’m not at all surprised that the author didn’t know, but am rather impressed to discover Mr Osborne did.

This volume apparently concludes, inter alia, that the rift between Geoffrey Howe and Mrs Thatcher was largely her fault, and that she did mislead the Commons over the Westland affair; a row about which helicopters to buy that I remember being complicated at the time.

That was when Mr Moore was editing The Spectator, which was in Mrs Thatcher’s corner, and doubted Michael Heseltine’s account. But at the time, all those involved had a strong interest in defending their version of events, and one of the most obvious disadvantages of journalism, when compared with biography or history, is that it’s not always easy to see the big picture when you’re in the thick of it.

Thirty years later, it may well be clearer who did what, when, where and even perhaps why. Obituaries, the biographies I produced, occupy a middle ground between the hurly-burly of news reporting and the careful, measured, scrupulously researched turf of the comprehensive biography. On the one hand, the death, especially if unexpected, gives them urgency. People want to read them the next morning or, nowadays, within hours if not minutes.

But they also try to be a kind of first draft of history. Death provides the end to the story, and with luck the shape of the life. On the other hand, very are much more than a thousand words.

Real history is much harder. I’m pleased that Mr Moore’s work is, as expected, being hailed as definitive. But what I really admire is his patience. I like to think that having to put up with me helped him in some small measure to cultivate that quality, so that the credit for his achievement is really mine, too.