Munster will play better over 80 minutes, presumably, but they'll rarely have to dig deeper as Castres confirmed they would be a much tougher nut to crack than in the sides' meetings last season. In the process, Munster confirmed that their collective character remains undimmed, though this scarcely needed confirmation given it is in the category of night following day.
Once again sheer force of will as much as technique or tactics subdued a much-changed, younger, stronger and more dynamic Castres, who have also unearthed a remarkable little goalkicker from Bergerac and the third tier of French club rugby in scrumhalf Romain Teulet.
As usual in these titanic Thomond Park struggles, big hearts and cool heads were required. When all else fails, Munster play for position first and points second, and these basic tenets were ultimately enough.
That they have become a victim of their success was put in perspective by Kidney:
"A victory such as today's three or four years ago would have been the highlight of our season. We basically have the same panel as we had three or four years ago, so we are absolutely delighted with today's win."
However, even Munster have to tinker with and improve personnel, and the value of acquiring Jim Williams was rubber-stamped by this defensively committed performance from the Wallaby.
Mike Mullins, too, looked the most dynamic back on the pitch, but, from an Irish international perspective, the most reassuring sight was that of Peter Stringer pulling the strings and clearing the ball away from the base and Ronan O'Gara's cool running of the show.
He landed seven out of nine and responded to the events of the previous week by invariably taking the right option and turning the screw with some sublime line-kicking. Returning to the bosom of his Munster family and the peerless man management of Kidney and Niall O'Donovan, this was not surprising, not least because of his own strength of character. Still, just because it was predictable doesn't make it any less commendable.
"That was definitely as tough a match as we've played in Thomond Park," admitted Mick Galwey.
As Munster extended their unbeaten European record at Thomond Park, it's tempting to take the Thomond factor for granted too. Yet there had been compelling evidence of what Kidney later referred to as "our 16th player" as they almost willed their team upfield.
There had, of course, been applause for the excellent Castres try by Ugo Mola. It came within six minutes of Jason Holland's well-taken score, when for once the Castres centres were checked by Anthony Horgan's dummy run and the outside backs drifted out for the Munster centre to spot the gap, and it left everyone in no doubt they were in for a long afternoon.
A barometer of the anxiety within Thomond Park's ranks is the extent to which they become agitated by the referee's decisions and seek to influence him. Admittedly, they had much to be animated about here, for Clive White's fastidious performance dominated proceedings and deprived the game of much of its flow. Unhesitatingly strict in penalising players for not releasing or going to ground, White was at least consistent and is a good referee. But it seemed excessively harsh when he whistled for accidental offside if the ball carrier merely brushed against a team-mate.
Nevertheless, a good example of the crowd's positive influence underlined perhaps the key moment of an ultra-tense second-half. O'Gara had just edged Munster back in front for the fourth time, just past the hour mark, when Castres came knocking at the door again.
Some impressive continuity was undone by a truly lamentable chip by Gregor Townsend, which gave Dominic Crotty ample time and, more importantly, a generous angle with which to gather, turn and punt downfield. Crotty's booming kick took play from inside one 22 to the other, and the huge roar emphasised its importance.
Munster upped the ante and went for the kill. By the time Castres lifted the siege and returned to Munster territory it was 28-20 and they were virtually beaten.
With a different referee Munster might have scored a decisive try when Stringer had the ball and the numbers before White called an end to their advantage under the Castres posts, and then ruled the scrumhalf's quick-witted tap penalty and skip pass to Clohessy had been taken from the wrong spot.
In any event, The Fields of Athenry went up, O'Gara landed a sweet drop goal and Romain Froment raced to the half-way line and kicked off straight to Marcus Horan in a frenzied manner which suggested that the French team were cracking.
O'Gara landed another penalty, and though Teulet would do likewise Munster had done enough again. With a little help from their 16th player.
SCORING SEQUENCE: Teulet pen 0-3; 12 mins: O'Gara pen 3-3; 20: Teulet pen 3-6; 22: Teulet pen 3-9; 26: Holland try, O'Gara con 10-9; 32: Mola try 10-14; (half-time 10-14); 43: O'Gara pen 13-14; 48: O'Gara pen 16-14; 51: Teulet pen 16-17; 54: O'Gara pen 19-17; 58: Teulet pen 19-20; 62: O'Gara pen 22-20; 67: O'Gara pen 25-20; 71: O'Gara pen 28-20; 80: Teulet pen 28-23.
MUNSTER: D Crotty; J Kelly, M Mullins, J Holland, A Horgan; R O'Gara, P Stringer; P Clohessy, F Sheahan, M Cahill, M Galwey (capt), M O'Driscoll, J Williams, A Foley, D Wallace. Replacements: P O'Connell for O'Driscoll (40-49 mins and 52 mins), M Horan for Cahill (52 mins).
CASTRES: U Mola; F Plisson, G Delmotte, N Berryman, S Longstaff; G Townsend, R Teulet; L Toussaint, R Ibanez (capt), B Moyle, F Laluque, N Spanghero, F Costes, I Lassissi, R Froment. Replacements: M Reggiardo for Moyle (56 mins), O Sarramea for Plisson (63 mins), E Artiguste for Mola (70 mins), S Chinaro for Laluque (74 mins). Sin-binned: Costes (12-23 mins), Froment (50-60 mins).
Referee: C White (England).
