When is a deadline not a "crude device" likely to prove "counterproductive"? Cynical unionists and angry republicans might venture the same reply: obviously when David Trimble decides he needs to set one.
On Thursday night a colleague welcomed the prospect of Mr Trimble's final showdown with his party's rejectionists. Hours before, he had watched the Ulster Unionist leader take the gloves off, borrowing Michael McGimpsey's words to ridicule Jeffrey Donaldson's "letter to Santa" with its "Christmas wish list".
It seemed Mr McGimpsey had prevailed in the battle for Mr Trimble's ear. Having agonised about a possible deal, Mr Trimble emerged from talks with Mr Blair with his mind apparently made up. The talks between the Assembly emissaries and dissident Donaldson were at an end; the stage set for a "back me or sack me" appeal to the Ulster Unionist Council.
Mr McGimpsey represents a significant section of senior unionists who believe Mr Trimble is at his least vulnerable when rehearsing the positive benefits of the Belfast Agreement for unionism, and that his ultimate security lies in the fact that not even the DUP seriously wants to bring down the Assembly.
Like Mr Ken Maginnis they also calculated that Mr Trimble should reject Mr Donaldson's disclaimers and insist this was an issue of leadership, certain in the belief the delegates would recoil in horror when confronted with the possible alternatives to Mr Trimble.
Following the Thursday evening press conference, held, amazingly, even as Mr Fred Cobain and Mr Danny Kennedy sought to finesse a compromise with Mr Donaldson, this appeared the settled strategy.
However, the colleague was offered a cautionary warning: there was no necessary connection between what Mr Trimble said on Thursday night and what he would do on Saturday morning.
A year ago, as he braced himself for the original decision to enter the powersharing Executive, Mr Trimble had firmly rejected what became known as the "post- dated resignation" option. In the final days before the Ulster Unionist Council meeting, however, he concluded he could not win without a deadline for decommissioning, and promptly set one.
The only certainty on Thursday night was that Mr Trimble, in the end, would do whatever he believed he needed to do to win. And so at the Waterfront Hall he defeated Mr Donaldson, but only after conducting a lightning raid on the Donaldson wardrobe and having attired himself in some of his opponent's garb.
Mr McGimpsey and others would certainly reject this take on Saturday's events. And it is true Mr Trimble did not explicitly spell out a timetable for his party's possible withdrawal from the Executive.
However, as John Hume constantly reminds us, perception can be as important as reality. Certainly anti-agreement unionists and Sinn Fein were swift to see a fresh deadline in Mr Trimble's commitment to reconvene the UUC in early January.
It is also possible to argue, as Prof Paul Bew did on radio yesterday, that Mr Donaldson may have peaked; that Mr Trimble's margin of advantage, up one point to 54 per cent, is the most significant outcome of a meeting called by the antis at what they considered their moment of maximum opportunity.
Arguable, yes, yet not entirely convincing. One pro-agreement Assembly member yesterday offered the contrary view: that Mr Trimble should be worried to manage just 54 per cent despite the promise of sanctions against Sinn Fein, the call for a moratorium on Patten, the promise of a more proactive role for Gen de Chastelain's decommissioning commission, and the assurance that the party can review its position again in January.
Interestingly, too, a British government source declined to avail of Prof Bew's positive spin. Mr Trimble, he said, would only have been entitled to assume the corner turned had he maintained his previous position and made no concessions to his hardliners.
The reality intended by Mr Trimble, and the highly influential Mr McGimpsey, may be otherwise. But the competing perception-cum-reality is that, in the minds of Mr Donaldson and Mr Gerry Adams, the Ulster Unionists turned the clock back on Saturday, all the way to last November.
That perception is augmented, too, by the fact that there is, at the very least, an element of conditionality attached to Mr Trimble's latest mandate which he successfully avoided when the council decided to re-enter the suspended Executive last May.
Prof Bew was right to acquit Mr Trimble of the charge, levelled by one Sinn Fein leader, of engineering a crisis designed to collapse the agreement, or at any rate force its institutions into suspension, ahead of next year's elections.
Some Whitehall mandarins also suspect this might be Mr Trimble's intention. Others, while acquitting him, harbour similar suspicions about his deputy, Mr John Taylor, who was not present at Saturday's meeting.
Those who know him best, however, are certain of one thing: Mr Trimble likes being First Minister. And those who, however reasonably, might question his motives overlook something even more important. Mr Trimble actually believes what he says about the Belfast Agreement; believes he won on Good Friday 1998, that the agreement has secured the Union, tied republicans to the principle of consent and a partitionist settlement, and Mr Donaldson and his allies are utterly and completely wrong.
So Prof Bew was spot on when he testified to Mr Trimble's desire to honour the agreement he entered into last May, explaining he had rejected the Donaldson motion because that deal did not require decommissioning within the timescale prescribed by the Lagan Valley MP.
However, that brings us to Mr Trimble's enduring problem in finally seeing Mr Donaldson off. Because that May deal does not require Sinn Fein to deliver IRA decommissioning within any prescribed timetable, and Dublin certainly does not consider next June any more a deadline that it considered May 22nd past.
The two governments will work flat out to persuade the IRA, in light of last week's statement, that the peace process would be enhanced by its serious re-engagement with Gen de Chastelain's commission. They may even hope to do so before Friday, when Mr Trimble's promise to bar Sinn Fein Ministers from attending North-South bodies will have its first test, since there may be a real risk now of a republican "tit-for-tat" withdrawal from Assembly committees, or possibly even from the Assembly itself.
Mr Trimble's strategy, however, requires much more than a resumed dialogue between Mr Brian Keenan and the general over tea and biscuits. The UUP leader's eagerness to avoid setting a deadline is accompanied by a determination that the general should. Yet it is not at all clear that Dublin or the SDLP will agree that he can, or that the provisions of the agreement would actually allow him to do so.
The gloomy assessment in both capitals will be that as a result of Saturday more is expected in a situation where less may be deliverable. There will be no moratorium on Patten. The sanctions against Sinn Fein may slide into a legal morass. And, when they reconvene in January, the Ulster Unionists must again decide if they are prepared to break the agreement over decommissioning. The indication from Saturday is that they well might.
