Four years ago, Welsh club rugby stood on the verge of a great revival. It went into round five of the Heineken European Cup pool stage with three teams - Swansea, Cardiff and Llanelli - leading their groups while Newport were still in contention in theirs.
Within weeks that promise was gone as Llanelli and Newport failed to qualify and Swansea and Cardiff crashed in the quarter-finals. It marked the end of the Welsh club system, the last time a structure whose teams once beat the All Blacks looked capable of matching the best of Europe.
This weekend brings round five once again, but in reverse image with the four Welsh regions on the verge of unprecedented failure. At least one Welsh team has advanced in all nine previous Heinekens.
Neath-Swansea Ospreys, Llanelli Scarlets and Newport Gwent Dragons are still in theoretical contention. But each stands third in their group and need two straight wins, including an unlikely victory away to a team that have already beaten them at home - the Ospreys at Munster on Saturday, the Scarlets at Toulouse and the Dragons at Newcastle next week - plus other results going their way, in order to progress.
Cardiff Blues are already out. They went into last night's meeting with Stade Français in jeopardy of a second winless campaign in three seasons, equalling Italian club Calvisano, who can plead tougher draws.
Accustomed to false dawns, Welsh rugby must hope this is a false sunset. Comprehensive elimination would damage the credibility of the new regional structure that was intended to restore competitiveness by concentrating talent.
It has worked in the Celtic League, where Llanelli were champions and other Welsh teams finished in the top half last season, while the Ospreys lead this year. But this achievement is compromised by the limited commitment of Irish teams.
The Welsh national team - intended as the ultimate beneficiary of change - also shows serious signs of revival. Yet it can be argued - and doubtless will, since the one thing Welsh rugby remains supremely good at is polemic - that this is down to new coach Mike Ruddock and blossoming players who came through the old club system.
What is really striking is how little has changed. With the close-season axing of the Celtic Warriors, Wales's four contenders are the same, nicknames and the Neath-Swansea merger apart, as in 2001, or throughout the last century when they were the four clubs that played touring teams.
This year has caught the system in transition, with Llanelli in decline and the Ospreys rising, but not yet sufficiently to match the best in Europe. Quite how little has changed is shown by the relative playing records of the two systems. Before this weekend the regions had won 20 and lost 26 Heineken pool matches - a success rate of 46.51 per cent. The clubs won 86, drew five and lost 99 - a rate of 46.58 per cent.
It is tempting to ask whether the upheaval was worth it. The answer is "not yet", but it is too soon for a definitive response. If, in five years, Welsh regions are still recording 46.5-something per cent success, and the national team is still finishing fourth or lower in the Six Nations, there might be a case for reverting to the old system. But for the moment the new structure needs time - exactly the commodity the Welsh Rugby Union was unwilling to grant the Celtic Warriors, the one region whose Heineken performance improved upon its predecessors, Bridgend and Pontypridd.