Is Gen. John de Chastelain about to work some magic? Might there be a "Millennium Dimension" to a fresh Mitchell deal? Will the next two months - while transporting us from one century to another - set the seal on Northern Ireland's "new beginning" and mark the decisive turning-away from the violent past?

Those who have already written off the Mitchell review will dismiss this as the stuff of fantasy. And they may, ultimately, be proven right. Senator George Mitchell is not there yet. Devils doubtless abound in the details still being worked through. Either party, or both, might still take fright and retreat.

However, the indications are that Sinn Fein and the Ulster Unionists really are tantalisingly close to a deal which would see the power-sharing executive, the North-South ministerial council and the British-Irish council up and running well before Christmas.

And if David Trimble is prepared to take the biggest risk - by jumping first and leading his party into government with Sinn Fein - there can be no doubt that the republican movement will be expected to cross its own particular Rubicon soon thereafter. A big bang on the Cavehill to see in the new century? Think of the power in that piece of symbolism.

Certainly if the Mitchell review is to have a successful outcome, then the available time-scale points to something of that order. The very idea will doubtless have some anti-agreement unionists reaching for the sick bag. However, given a deal, or the outline of a deal this week, we can expect much to be made of "the millennium challenge" as politicians on both sides battle to generate the excitement and momentum with which to carry through the changes at which they have balked these past 17 long months.

But we're getting ahead of ourselves. The new millennium is still some eight weeks away. This week should tell whether the countdown will be marked by high hope and political drama, or by the weary realisation that the dreary steeples will still dominate the North's political landscape.

For the moment at least the pointers are with the optimists - the strongest, arguably, the very secrecy surrounding the ongoing negotiations. There has been nothing like it in all the years of talks and talks-about-talks. Nor, as might have been first thought, is it merely a matter of parties not wishing to offend the senator. Those in the know say the quality of the engagement between Sinn Fein and the Ulster Unionists has been outstanding - and that Senator Mitchell himself has "played a blinder", not least by giving the parties as much time as they have needed.

Those senior British sources who had the review coming to an end two weeks ago clearly misjudged their man. The senator will not fail for want of patience. It is in that context, perhaps, that we should consider Mr Trimble's injunction not to think in terms of any particular "make or break" week. And the primary message from Mr Trimble's American jaunt was that he is not contemplating failure.

At Stormont this afternoon Senator Mitchell will resume the drive for success - agreement between Sinn Fein and the Ulster Unionists on a sequence of events which would lead over a period of weeks to the triggering of the d'Hondt procedure for the appointment of ministers.

We have long known the UUP prescription for making this happen: a statement from the IRA confirming the war is over, agreement to produce an inventory of the weaponry in its possession, and a commitment to decommission by May 2000 in accordance with the timetables and procedures set by the International Commission.

Mr Trimble must know that, if it is to happen, it will not be like this. He will also know from past experience that if and when the republican movement speaks, it will be in language of its own choosing. The likeliest outcome might be a combination of words (from Sinn Fein) and actions (by the IRA). Is it impossible, for example, for Sinn Fein to state its belief that the implementation of the agreement, already endorsed in a dual act of self-determination by the people North and South, would spell the end of the conflict?

Could such an assertion be coupled with a restatement of the party's commitment to all the original Mitchell principles, including a repudiation of any attempt by any others to oppose the Good Friday settlement other than by peaceful means?

And might "P O'Neill" break silence long enough to endorse Sinn Fein's position, while confirming that the IRA is appointing an interlocutor to mark the beginning of the decommissioning process?

WHATEVER is to come, we may be very sure of one thing: any words or deeds will be tailored to meet the republican movement's own clear interpretation of what is required by the Belfast Agreement. Senior British sources, too, continue to caution that unionists must frame their demands in those terms - of decommissioning "as an obligation, not a precondition."

Some senior Ulster Unionists appear to have got their heads round the concept that any decommissioning will have to be presented as "voluntary". So too, they respond, is entering the executive. And they are unlikely to quibble if any republican commitment to Gen. de Chastelain provides what Mr Peter Mandelson defines as "certainty of intention".

Almost certainly it is upon the quality of any such commitment that the prospects for success or failure turn in the first instance. However, the second decisive factor will be whether Mr Trimble can bring his party with him.

The party's "jumping together" policy might allow a little flexibility, perhaps in terms of days, between the formation of the executive and an actual start to decommissioning. Certainly any significant delay would be interpreted as a change of policy, requiring party approval.

And in any event, Mr Trimble's anti-agreement opponents would almost certainly treat anything other than simultaneous decommissioning as the trigger for the long-awaited showdown. Hence the growing belief, as previously reported in The Irish Times, that Mr Trimble will seek to pre-empt his opponents by himself calling a special meeting of the ruling Ulster Unionist Council to endorse any agreement reached in the Mitchell review.

But again, we are in danger of moving ahead of the game. Mr Trimble may be prepared to meet his rejectionists head-on. However he is unlikely to see his party implode until and unless the republican movement makes him an offer he feels unable to refuse.

The internal arithmetic still raises a huge question mark over the viability of this proposed partnership. Without question the greater risk in the long run is to the Ulster Unionist leader. And if the dance is to be on, the republicans still have to make that first all-important move.