The resumption of European battle this week comes with the PRO12 contenders setting the pace after winning nine of their 14 ties over the two opening rounds, out-performing their Anglo-French challengers from the Top 14 (six wins in 12 ties) and Aviva Premiership (five wins in 14 ties).
For Munster, the trauma of losing twice at home in the opening month of the season is but a distant memory. Their win over Ulster at Thomond Park has completed their recovery from a wobbling start to the resumption of usual business in a familiar landscape - top of the PRO12.
Since the Ospreys won in Limerick at the end of September, Anthony Foley's team has responded with seven wins on the bounce - starting with Leinster at the Aviva Stadium in front of almost 45,000 and in the period between that match and last week's against Ulster they reeled off a Welsh treble, beating the Scarlets, Blues and Dragons in that order.
The sequence also includes two wins from two in the Champions Cup against English opponents - Sale Sharks away by a point and Saracens at home by 11. For their next assignment, Munster will be defending a record of invincibility against French clubs in Limerick.
Bourgoin were the first to bite the dust, way back in September 1997 when John Lacey from Tipperary scored the only try of a close game - the same John Lacey who handled the Wales-South Africa match last weekend in this his third season as an international referee.
A total of ten French clubs have made 21 visits to Thomond Park in European competition and lost the lot. Nor does familiarity seem to make the task any easier, Castres having lost there five times, Perpignan four and Bourgoin three.
Clermont will be making their third trip. They lost at the pool stage seven years ago during the season that ended with Munster crowned champions of Europe for the second time.
They returned one year later and lost again, albeit narrowly on another of those nerve-wracking finales which have made Thomond Park the supreme theatre for high drama.
With barely two minutes left, the defending champions were losing 13-11 against opponents down to 14 men since the opening quarter. An altercation between the super-heavyweight second rows, Jamie Cudmore and Paul O'Connell, ended with the English referee, Chris White, giving Clermont's Canadian a red card and the home captain a yellow one.
Munster, never more dangerous than when time is running out, scored two tries in two minutes from their pack. Marcus Horan got the first and Niall Ronan's famous chip-and-chase stripped Clermont of the consolation of a losing bonus point.
In contrast to Munster's seven straight wins, Clermont have lost their last four on the road - at Toulon (19-27), Bayonne (13-24), Bordeaux-Begles (21-51) and at Saracens (23-30) in the opening round of the Champions Cup.
While Munster lead the charge of the unbeaten PRO12 teams on Saturday, Glasgow Warriors and Leinster go into action on Sunday at Toulouse and Harlequins respectively, each seeking a third win in three matches.
Guy Noves, Toulouse's perennial head coach, remembers only too well what happened when the Warriors paid a visit six years ago and won 33-26 courtesy of three tries and seven goals, all from Dan Parks. That they have already won in southern France this season will make Noves warier still.
The Warriors cast may have changed but nobody has made a more impressive start in Europe than the Glaswegians - running five tries in against Bath at Scotstoun and following that with a real statement of intent in Montpellier where five Finn Russell penalties did the trick.
Leinster, unbeaten in their six matches since losing to Munster two months ago, revisit The Stoop eager for a second English scalp to follow that of Wasps, beaten 25-20 at the RDS in mid-October when Darragh Fanning's two tries on his European debut helped the former triple champions come from behind. Harlequins have had nothing more than six Nick Evans penalties to show for their last two losing matches against Sale and Bath.
Ospreys, reinforced by the return from Test duty of, among others, their in-form half backs Dan Biggar and Rhys Webb, know they must make home advantage tell against Racing Metro at the Liberty Stadium on Saturday.
Treviso, heartened at having gone within a whisker of beating Leinster in their drawn match on October 23, are home to Northampton Saints.
The one all-PRO12 tie, Ulster against Scarlets, follows in Belfast on Saturday night. Their last meeting, in Llanelli on the first day of the season back in September, ended level on tries (4-4) and points (32-32).
They also share something else in common. Each has lost to Toulon in the opening rounds, which gives neither much room for further error.
Both ought to be encouraged by the fact that GUINNESS PRO12 clubs have qualified for the quarter-finals more often than those from the Aviva Premiership and Top 14. Of the ten clubs to have qualified for the last eight of European competition over the last eight seasons, half of them come from the PRO12.
Most quarter-finals since 2006-7 - PRO12 teams in caps:
1-MUNSTER 7
2-LEINSTER 6
3-Toulouse 6
4-Leicester Tigers 5
5-ULSTER 4
6-Clermont 4
7-Saracens 4
8-OSPREYS 3
9-CARDIFF BLUES 3
10-Toulon 3
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