Rory Bremner was on his best behaviour; Charles Kennedy, the leader of the Liberal Democrats, leaned forward to kiss the Chancellor's wife Sarah Brown on the cheek.
Mr Cook's widow, Gaynor, arrived at St Giles' cathedral moments later with Mr Cook's sons, Peter and Chris. Looking pale, she was greeted by Jim Devine, Mr Cook's agent, who gave her a large embrace. Cook's former wife Margaret was also there, arriving some time before the service began.
Senior figures such as the Deputy Prime Minister, John Prescott, the Foreign Secretary, Jack Straw, and the former Labour leader Lord Kinnock of Bedwelty were joined by other statesmen including the German Foreign Minister, Joschka Fischer.
Tory MPs were also present - the former Tory foreign secretary Malcolm Rifkind, an old university friend, anxiously surveyed the ranks of suited and booted Labour backbenchers for a bench of his own.
Cook's parliamentary colleagues, meanwhile, were wondering openly what they were to do next, swapping anecdotes that gave short shrift to the fiction that Cook didn't suffer fools gladly. For some fools were present, not least Cookie's old friend from the turf, John McCririck. His broadside, his savaging of Tony Blair from the pulpit of St Giles for "snubbing Robin by staying on holiday snorkelling", brought forth an audible sigh from Labour's clans.
"We all think it," said one senior backbencher afterwards, "but we don't need to say it. Robin wouldn't have liked that."
There were more fond tributes from Richard Holloway, the Scottish Episcopal Church's former bishop of Edinburgh. He told mourners how Mr Cook's son Chris received a text message from his father just an hour before he died. "Am at top of Ben Stack, view of Arkle and Foinavon can't be seen for mist - weather foul. Wish you were here."
Mr Holloway said: "He was on the rooftop of Scotland with the woman he adored, he was thinking of the sons he loved with all his heart, he was making a joke about the Scottish weather and, for those in the know, Arkle and Foinavon are peaks which two famous steeplechasers were named after."
What was lacking on the Blair front was more than compensated by the tour de force delivered by Gordon Brown, Cook's colleague and sparring partner of a quarter of a century.
"Robin was a friend to me when I started out as a tutor for the Workers' Education Association," reminisced Brown, "even when my first lecture was heard by just one student - and my second by none."
The Cook and Brown story is one of what might have been. Instead, their legendary rivalry drove them apart. But they had made it up some time ago. They both perhaps realised that they could achieve more together; that this came too late is a tragedy of modern politics. "To paraphrase Sophocles," reflected Brown, "we must wait till the evening to see how the day has been."
For a while it seemed that everything could be mentioned, would be mentioned, but the war. But it would come - notably in Mr Brown's eulogy.
And the Labour MP Mohammed Sarwar told the mourners how Cook was one of the few politicians to be trusted by Britain's Muslim community.
The gathered Labour Party, riven and reduced by the rest of the Cabinet's failure to follow Cook's lead over Iraq, looked on in silent reflection.
All, however, will miss Cookie. More perhaps than they will know.Reuse content