Last-minute nerves are nothing new in Northern Ireland politics. At the moment they are more apparent on the unionist side. For a long time, UUP members have given the impression that they do not want the current dispensation and feel it has been foisted on them as part of the sequence which began with the first Hume-Adams meetings.
Given its genealogy, the peace process was never going to get a welcome on unionism's doorstep, but the power of the pan-nationalist alliance forced London to bring its Northern Ireland clients into line. Few unionist politicians seem to have lost a night's sleep over the mistreatment of the nationalist population, but the paymaster in London wanted them to sign on for certain changes. It was a case of "go with the flow".
There were bound to be times when it was hard for unionism to follow the new agenda. Going into government with the republican movement was never going to be easy. The more one looks back on it, the more the 72-day Executive at the turn of the year seems like a miracle. The wonder was not that it lasted such a short time, but that it happened at all.
UUC delegates appear to be heavily focused on what they consider the negative aspects of the Belfast Agreement: republicans in government, institutionalised North-South links, compulsory power-sharing and the IRA still in existence. In their new-found political victimhood, they seem blind to other more "Union-friendly" elements of the package: Stormont restored, Articles Two and Three modified, minimalist cross-Border bodies, consent acknowledged, IRA guns not only silent but subject to outside inspection.
It has been taken on trust that, once the IRA took a vow of silence and Dublin guaranteed the continuance of the Border for as long as a Northern majority so desired, the more progressive elements in unionism would see the practical common sense of entering day-to-day working arrangements with their nationalist and republican neighbours. But unwelcome fears are beginning to return that this was never about guns or violence and that there might be some truth in the charge that significant elements of unionism simply did not want a "Fenian" about the place.
Early yesterday, hints were emerging that the UUC meeting planned for Saturday could just conceivably be postponed. As the day progressed, and especially after some soothing words from Mr Blair and Mr Mandelson in the Commons, it looked as if the meeting would go ahead after all.
The implications of postponement would be serious. The IRA offer on weapons might well be taken off the table. We would be back to square one but with the vital difference that this time the impasse would not be blamed on republicans' refusal to decommission but on unionist obduracy and short-sightedness.
If the unionists could not come on board for the latest negotiated package, then what was previously unthinkable might become an item on the agenda; some sort of "imposed solution" could hardly be out of the question.
Mr Mandelson has been bending over backwards to appease unionism on policing and flags. In the process he has aroused nationalist and republican anger: whether he has also secured a victory for Mr Trimble at the Waterfront Hall remains to be seen.
The SDLP has been making much of the running on the police issue: a party delegation met the Northern Secretary on Tuesday, with Mr Seamus Mallon expressing his views in characteristically robust fashion.
Meanwhile, the DUP watches from the sidelines. There is said to be a lively debate within its ranks on whether to take up its two ministries if the Executive is set up again. The basic question to be resolved this week is this: if the Belfast Agreement went ahead despite the variety and complexity of the issues involved - prisoners being perhaps the most emotive - how can the process come unstuck at this stage over names, badges and flags?