Certainty, and the lack of it, is concerning nationalist and unionist negotiators as the ingredients of a potentially historic deal to bring about the full and final implementation of the Good Friday Agreement are being put in place.
The weekend saw two significant developments in the ecclesiastical capital of Armagh.
Ulster Unionist leader David Trimble showed a willingness to face down his internal critics and accept a compromise on some of his party's most hardline demands. Meanwhile, across town, a Sinn Féin leader went further than ever to a statement that 'the war is over', a necessary first step towards a similar statement by the IRA.
Sinn Féin chairman Mitchel McLaughlin significantly called for the "legacy" of the conflict to be addressed, "now we have ended the war in our streets".
Both communities are being prepared for, and guided towards, a major transformation in the North's ailing political dispensation.
A deal is being sought to pave the way for elections to the Belfast Assembly, the restoration of devolved power-sharing government in the Six Counties, and the full and final implementation of the 1998 Good Friday Agreement.
The deal is being negotiated in the teeth of what is likely to be a fraught, but long overdue, election campaign. And while the outcome of the election remains uncertain, and with internal and external pressures building once again on both Sinn Féin and the Ulster Unionists, an unprecedented level of mutual trust will be required to deliver a deal which could rival the Good Friday Agreement itself.
But with important details still unresolved, negotiators are wary that the current 'high-wire' act could come crashing down at any time.
A similar set of negotiations came unstuck in April over the form of words to be used by the IRA. The impossibilty of convincing unionists of the IRA's sincerity and goodwill is one reason behind the interminably escalating demands of unionist hardliner. Their insatiable demands have included a call for a theatrical display of IRA disarmament and a statement detailing the activities in which the IRA will cease to engage.
On the republican side, the continuing flexibility of David Trimble's attitude to the Good Friday Agreement -- and his on-off alliance with his party's hardliners -- stymied the negotiations once again last week and continues to worry Sinn Féin negotiators.
Trimble's manner of party leadership following the expected election, if it even continues, is a source of huge uncertainty and concern. There is also the possibility that an indecisive election campaign by Mr Trimble could allow ultra-hardliner, Ian Paisley, to become the dominant unionist figure in the Stormont Assembly -- a doomsday scenario for all those involved in the current negotiatons.
Paisley predicted today that the Ulster Unionists would take "a battering" at the next Assembly election. He was mocking the new branding of the Ulster Unionists -- no longer the Ulster Unionist Party -- who today launched the first in a series of posters marking their new slogan "Simply British", with a picture of a plate of fish and chips.
Paisley asked of Trimble: "Is he honestly saying that to allow the likes of Martin McGuinness back into government now without a definitive end to IRA activity is clear enough ground upon which to move forward?"
Meanwhile, his deputy Peter Robinson was standing shoulder-to-shoulder with Ulster Unionist hardliner Jeffrey Donaldson following a meeting with PSNI police chief Hugh Orde.
Speaking to reporters, Donaldson said that it was "becoming difficult" for him to continue to fight for what was right within the Ulster Unionist Party. He expressed particular concern over plans to devolve policing and justice powers from London to Belfast, an issue not coincidentally reported to be holding up the deal.
He said: "I have to say that I am very concerned that some kind of a deal is being cooked up here, that it involves the devolution of policing and justice powers within two years.
"That is something the Ulster Unionist Party has never discussed. Mr Trimble hasn't consulted the party officers about this two-year timescale.
"It also seems that our requirements on decommissioning and the disbandment of the IRA are once again being watered down.
"I think we are looking at another fudge and in such circumstances I believe a deal of that nature will be rejected by the overwhelming majority of Unionist voters."
Mr Donaldson was one of three dissident MPs who took an independent stance at the British parliament in June in a row over party policy.
In his address to the Ulster Unionist conference on Saturday, Mr Trimble challenged the three MPs to decide if they wanted to remain within the fold and abide by party orders or become independent.
Mr Donaldson insisted today that he intended to run as an Ulster Unionist candidate, having been selected by the Lagan Valley constituency for the Assembly election.
But there have been suggestions that selected candidates may not be allowed to run for the Ulster Unionists without a promise to abide by party policy, something which Mr Donaldson and others have resisted.
Mr Donaldson countered this by suggesting that in the forthcoming election, Ulster Unionist candidates might take their own position on any peace process deal.
"It certainly seems at the moment from what Mr Trimble was signalling at the weekend that the deal is going to fall short of the requirements that we have laid down," he said.
"In those circumstances, each candidate will have to make their position clear as to whether or not they support that particular deal."
The Ulster Unionists were expected to have more talks today with Sinn Féin as efforts continue to bridge the remaining gaps between them.
Sinn Féin negotiator Conor Murphy said that the talks had reached a sensitive point.
"I think we are at the make-your-mind-up stage. I don't think it would be sensible of me to make any predictions about what may, or may not happen, in those circumstances."
With speculation intensifying that the British government will announce a date for Assembly elections in late November in any event, Mr Murphy said republicans wanted the poll to take place in a positive climate.
"Political will is the trigger," he said. "That is what we are calling for.
"We think that, if the political will is there, things can be done and we certainly hope to play our part in ensuring that we do go into an election in a positive frame of mind and we do get the institutions back up and running and the Good Friday Agreement fully implemented."
While Mr Trimble today warned against calling Assembly elections without the agreement of his party, no major disagreement has emerged from the talks.
Sinn Féin President Gerry Adams and chief negotiator MMartin McGuinness are will resume meetings with the Ulster Unionist delegation including Mr Trimble and Reg Empey later today.
It is believed that Wednesday remains the final deadline for the intensive discussions.
Despite British Prime Minister Tony Blair's health scare last night, he is expected to join Irish Prime Minister Bertie Ahern in Belfast if a deal is ready to be unveiled.