Matthew Norman: Welcome back, Keith! We've missed you!!

What a glorious week it has been for our sceptred isle's favourite sport! The first days of July are always a high point for professional nostalgism, in truth, but this year footage of Borg and McEnroe swinging their quaint wooden rackets through that monster tie-breaker of 1980 has for once been obliged to take a back seat.

This week's relaxing bath in the Badedas of yesteryear has been drawn for us by the veterans of politics, specifically from the party within a party of which much too little has recently been heard. New Labour is back in the news, via three of its most lovable characters, and by all the saints it's bliss to welcome it home.

Over in Brussels, Peter Mandelson enjoys a startling return to form in the game of Publicly Taking Umbrage at which he once headed the rankings. Not since the last time he was resigned, over the Hinduja brothers' passports, has he performed the Kenneth Williams nostril flare of indignation with such resentment as he lavishes on Nicolas Sarkozy's attack on his negotiating skills as EU trade commissioner. Little is more heartwarming than an ageing former champion enjoying an Indian summer, this one bringing to mind Jimmy Connors' outlandish 1991 run to the US Open semi-final aged 39. Who had remembered that he was still in the game at all?

Yet even Mandy's renaissance is relegated to a sideshow by two erstwhile colleagues from the glory days of yore. You may have had some vague sense that Geoff "Buff" Hoon, who as defence secretary learned that the invasion of Iraq had begun by a TV report, was still in the Government in some capacity or other, but did anyone ever expect to hear from Keith Vaz again?

In attempting to deconstruct the letter in which Geoff thanked Keith for reversing his position on the 42-day detention period and voting with the Government after all, I confess my inadequacy. The only hack properly qualified to analyse its meaning is Lynne Truss, for it turns entirely on a matter of punctuation.

And so, with that pre-emptive rider in mind, to the text of the hand-written missive so mysteriously leaked to David Cameron, who ambushed Gordon Brown with it at Wednesday's PMQs. "Dear Keith," wrote Buff. "Just a quick note to thank you for all your help ... leading up to Wednesday's vote. I wanted you to know how much I appreciated all your help."

Note the clever use of dramatic repetition. If Keith retained any doubt that was being thanked for his help after the first sentence, Buff had expertly removed it by the end of the second. And they say he isn't all that bright. "I trust it will be appropriately rewarded! With thanks and best wishes, Geoff."

So what are to make of that "dog's cock", as the exclamation mark is elegantly known in newspaper offices? Was it merely a waggle of excitement from a chief whip at a great Commons triumph in which Keith played his part, or the spraying of Westminster bushes with the noxious scent of a bribe formally acknowledged? Was Buff using it ironically in furtherance of what he claims was a private joke? Or was he emphasising that a promise of a sword tap on the Vaz shoulder, or even the draping of ermine over the Vaz back, would not be forgotten?

On the interpretation of that "!" all depends, but sadly the indications are mixed. On the one hand, there is no suggestion in Ms Truss's Eats, Shoots & Leaves that the exclamation mark is an acceptable device to display ironic intent. On the other, Geoff Hoon seems less a talented grammarian than the kind of good-natured dim wit who would pepper his prose with them in the belief that appending "!", or even "!!", to any sentence retroactively imbues it with the essence of Wildean wit.

I must confess to bafflement. The denial from Gordon that he offered any bribes before the vote on which his survival depended, although clearly a useful hint, isn't technical confirmation that bribes were offered. Gordon says that being thanked for his help was appropriate reward for Keith in itself, and who's to say this isn't the plain truth?

Who, come to that, is to say that the Democratic Unionists didn't have a collective Archimedes moment in which all nine of them simultaneously saw the hitherto hidden wisdom of 42 days? Telepathic osmosis is, as Jimmy Greaves observed, a funny old game. It could well be that Keith, having opposed 42 days as chairman of the home affairs select committee – a post in which he must have been au fait with all the arguments for ages; and from which he was doubtless particularly helpful in persuading others not to rebel – had a similar epiphany.

Certainly he has a proud record so far as the dramatic volte-face is concerned. Last summer, he had letters about an EU referendum published in two newspapers within a month. "There is no need for a referendum," he wrote to The Daily Telegraph on 30 July. "As a former minister for Europe, I believe the time has come for the Government to hold a referendum...," he told Sun readers on 31 August. Such winsome elasticity of mind would extend to a change of mind on 42 days without a sniff of the knighthood he is now less likely to receive, as a result of this dispute, than Abu Hamza!!

Then again, he has equally impressive form for dodginess, having once been suspended from the Commons for a month over sleaze allegations, and lost that Europe portfolio in the wake of the same Hinduja affair that did for Mandy. He would dispute this, insisting that the alleged sleaze was oversight rather than naughtiness, and that he resigned because of ill health. "Heart problems" was the official explanation at the time. A few days later, I rang his constituency office in Leicester to rearrange an entirely fictitious game of squash. "Right," said Alison, his secretary. "Next Sunday, then. I'll get a message to him."

Even if Keith's apparent untrustworthiness and fabled opportunism suggest an answer, we will never be absolutely sure about the meaning of that exclamation mark. And yet his unexpected reemergence as a national figure, however brief, gladdens the soul. His lack of belief in anything but his own advancement renders him as powerful a New Labour archetype as Geoff Hoon's relentless sycophancy to power makes him, and Peter Mandelson's ungodly capacity for queeny public skirmishing makes him.

Together this trinity reminds us of a gentler age when we were all borrowing like maniacs in the knowledge that there would no return to boom and bust, and when Mr Tony Blair brushed off impertinent questions about minor corruption from Tory leaders with all the smiley insouciance at his disposal. Ah such happy times, to borrow from the late Karen Carpenter, and not so long ago!!!