Now we know why Tony Blair looks so comfortable on the chat-show sofa: it's home from home. As the Hutton and Butler inquiries have revealed, the Prime Minister prefers intimate, informal chats on the sofa to the discipline of minuted cabinet meetings.
His chief of staff, Jonathan Powell, told Lord Hutton that, out of a possible 17 meetings on an average day in the run- up to the Iraq war, at only three would proper minutes have been taken. But then, you never took minutes when you went round to Gran's for a cup of tea and a natter, did you?
Blair's admirers claim he has a feel for the prevailing mood and instincts of voters. Perhaps this attachment to the sofa is an example of his common touch. Like the rest of us, he longs to kick off his shoes and settle back. Maybe he has been inspired by the many TV sitcoms that, over the years, have revolved around the sofa - not least Till Death Us Do Part, which starred his father-in-law.
Sofas matter. They are central to British life, a national obsession. The number of advertisements for new sofas - from DFS, Ikea or Multiyork - is proof of that.
Yet we need the skills of a Leo Abse (the former Labour MP and follower of Carl Jung who wrote Tony Blair: the man behind the smile) to explain the strange appeal that the sofa holds for the PM. Perhaps, as with many men educated at an all-boys school, Blair sees the sofa still offering up a certain erotic charge, the prospect of amorous fumblings with blushing young girls. (Or is that just me?) The cabinet room, favoured by John Major as a place to work, is a chilly and cavernous place. Blair's "denocracy" is altogether more personal.
Other questions arise. Is the PM's sofa a two- or three-seater? Does it add to the complications of his relationships with colleagues such as Peter Mandelson and Gordon Brown? There are, after all, three of them in this marriage, so it's bound to get a bit crowded. Perhaps we will see a return to cabinet government only when a designer comes up with a 20-seat sofa that could accommodate all these political forces.
Class inevitably enters this debate, too. Here we need Nancy Mitford's help. Does Blair work in a drawing room or a lounge? Does he sit on a sofa or a settee? After a misunderstanding during school assembly many years ago, my friend Richard Herring spent much of his youth singing "Lord of the dance settee", instead of "Lord of the dance said he", as the composer Sydney Carter intended.
When Blair spoke to the film-maker Michael Cockerell a few years ago about his aversion to lengthy cabinet meetings, the PM's face broke into that familiar, boyish grin of incomprehension. Why would anyone want to sit in cabinet for hours on end, discussing the nation's affairs? What crisis could possibly be so great nowadays that could justify taking up so much of everyone's time?
In Blairworld, the cabinet is not the place for drawn-out debate. The greatest threat to its erstwhile primacy has clearly not been the insatiable, round-the-clock media in Britain, but Tony Blair's fondness for his sofa.