Mary Dejevsky: Why not call Blair now and wrap up the affair?

The Iraq inquiry, with the length of time we waited for it, the projected timetable of a year and the special logo designed for it in serious blue, all seemed to promise a fierce sense of purpose and formality to match the grave act of taking the country to war. Somehow, even by day four, it doesn't feel like that.

For the Queen Elizabeth II Conference Centre, the inquiry already seems like a sideline. The centre's main gig yesterday was a medical conference for which you received a big white and red badge. For Iraq, you were handed a more discreet black and cream badge, on presentation of ID and your signature, before progressing through an X-ray security machine on the second floor.

Perhaps because it was Friday, the Great British public was hardly jostling for space. The queues of day one and the protesters in carnival masks were long gone. The inquiry room was chilly, as though they had switched the heating off a bit early for the weekend, and barely a third full.

Watching Sir Jeremy Greenstock, once our man at the United Nations, being put through his very deliberate and carefully judged paces, was a small and scattered audience of more women than men, with more grey hair than brown or blonde, and accoutred with woolly cardies, boho bags, some thick novels and, in one case, some colourful knitting. The quiet click of the needles and the distant strikes of Big Ben were the only background noise, after our attention had been drawn to the emergency exit provisions.

Sir Jeremy – unlike, it was whispered, the star of the previous day Sir Christopher Meyer (he of the red socks and the indiscreet memoir D.C. Confidential) – did not keep the inquiry waiting. He was ushered in through a side door and took his seat before the committee. I wouldn't say he had a spring in his step, or that he looked delighted to be there. For the three hours that were allocated to his evidence, there was a distinct air of duty before pleasure in his demeanour. There were no verbal or behavioural fireworks either, and no familiar joshing with the panel of the sort seen at times on previous days. Comparing Sir Jeremy's fastidious use of language and the way he parsed each question before he answered it with Sir Christopher's laid-back jocularity, you had to marvel that two such opposite characters had found their way to the top tier of British diplomatic service.

Sir Christopher had batted back one remark about a point being merely "a detail", saying: "Christ, the devil's in the detail." It was impossible to imagine anything like that jovial profanity passing Sir Jeremy's solemn lips. Yet small print and exactitude were, in fact, what the evidence of both of them was all about. Knowing now what we could suspect, but not actually know, as the events of 2002 and 2003 were unfolding, several distinct timetables were proceeding at once, all at odds and all fatally destined to collide in war.

There was the US domestic political timetable, the military preparation timetable, the weapons inspection timetable, and the UN diplomatic timetable. In the end, the US President's military agenda meant everyone else just ran out of time. Was the US military tail, in effect, wagging the diplomatic dog, Sir Jeremy was asked – in a form of words introduced by our former man in Washington the day before. "Of course," said Sir Jeremy, stone-faced.

The former ambassador to the UN kept the same gnomic expression of calm that he had preserved throughout the ever-rising tension of February and March 2003. But there was a grimness and intensity about some of what he said, and every now and again a hint of impatience with some of the more vapid questioning and the apparent ignorance of either the UN or his craft it betrayed.

Sir Jeremy could not have known it, but when at one key point he mentioned "diplomats", the bizarre combination "dim mat" scrolled on to the automatic transcription screen. I'm not sure he would have appreciated the neologism, even if he had seen it.

The inquiry opened to widespread scepticism that anything new or useful would come out of it, and not just among the chattering classes that Tony Blair, frustrated by his difficulty in "selling" the war, dismissed as the Islington dinner-party set (after he had ceased to live there). And there is already much editing of the past.

Take Sir Christopher: as he told it, an astonishing number of his memos seemed to have fallen victim to a particularly negligent Foreign Office archivist. Or take Sir Jeremy: despite the cataclysmic defeat for British diplomacy that was the failure to secure a second UN resolution sanctioning the use of force, he insisted yesterday that the British had emerged with something like an A for effort that had helped the post-war diplomacy along. Maybe it did.

To a British public more used to the cut and thrust of Prime Minister's Questions on a good day, or Paxman-style interrogations, this inquiry will seem a gentle affair. Then again, it is not supposed to be adversarial, but to seek truth that is already receding into the past. It is tempting to ask why they don't simply bring on Tony Blair, as chief witness and protagonist, right now – and have the whole thing wrapped up by (this) Christmas.

Chilcot Inquiry: Mary Dejevsky’s verdict on the panel

Sir Roderic Lyne

A former diplomat, who retired as ambassador to Russia in 2004. Wide range of academic, administrative and business interests: he's a non-executive director of Peter Hambro Mining and governor of Ditchley Foundation, which is headed by Sir Jeremy Greenstock.

Verdict: Sharpest questioner, with the best grasp of diplomatic niceties. The one who unsettled the first-week witnesses most.

Baroness Prashar

A cross-bencher in the Lords since 1999, she has been a Civil Service Commissioner and chair of the Parole Board. Born in Kenya and educated in Britain, she sits on several committees in the House of Lords.

Verdict: Long and occasionally fuzzy questions that at times irritated Sir Jeremy with their apparent lack of focus. Seemed less than well versed in diplomatic procedure.

Sir John Chilcot

A career civil servant and pillar of the establishment who retired in 1997 after seven years as permanent undersecretary of state at the Northern Ireland Office. He had previously served as private secretary to three home secretaries. Member of Butler review panel.

Verdict: An authoritative chairman and also the most incisive and seemingly best-informed questioner to sit on the panel.

Sir Lawrence Freedman

Professor of war studies at King's College, London, and author of books including the official history of the Falklands campaign. Drafted Blair's Chicago speech in defence of liberal military intervention. Criticised Bush's conduct of the war, but not the war itself.

Verdict: quietly exact and well-informed questions on specific points, rather than principles.

Sir Martin Gilbert

Wide-ranging author and official biographer of Winston Churchill. A human rights activist, Sir Martin also campaigned for Jews to be permitted to emigrate from the Soviet Union. As a historian, he tends to compilation rather than argument.

Verdict: Asked a few, narrowly focused questions of detail. The quietest member of the committee, at least at this stage.