Between power and vulnerability, there must be a balance.
Three years ago, John Kelly recalls that he felt physically sick before their Heineken Cup semi-final meeting with Leinster. He need not have bothered. Then, Leinster succumbed to the same virus that struck Munster this time around.
How the worm turned. On Saturday, for all their Grand Slam experience, their European pedigree, their Lions call-ups, their coaching expertise, Munster fatefully lost control of the balance between their awesome power and the vulnerability that innately must strike at the heart of even the most indomitable sporting force.
That was only a portion of this fascinating tale. For Munster to fail, it also required as its irresistible catalyst a Leinster performance of unshakeable belief, clinical precision and intense ferocity, the likes of which their support had never seen before.
Never, at least, in the one afternoon.
Within the compass of this 80 minutes, Leinster re-routed all the distracted, inconsistent, fractured European outings of the past three years, dating back to that dismal defeat at the penultimate stage three years ago, into their most coherent performance since; their most complete display in all facets at precisely the moment that it was required.
Brian O’Driscoll captained the side which slumped here three years ago; misguidedly he chose to signify Saturday’s occasion as one where his side answered their critics. The warrior was wrong. His side had responded to their own demons.
“I don’t think it was necessarily 2006,” he said when asked about his side’s motivation.
“We’d lost twice to Munster this season and we really felt that we owed them one.
“I think people had questioned our integrity and our pride by questioning our passion, and I thought we produced a big, passionate performance today to try and quieten those detractors.”
Like a boxing re-match which turns stunningly and violently by 180 degrees, Leinster’s winning margin on this mammoth European occasion was merely five points short of replicating the scoreline of three years ago.
“The scoreline doesn’t really reflect the closeness of the game,” admitted their enormously resourceful captain, Leo Cullen.
“When we’ve played Munster this season, they’ve won by similar scorelines and they haven’t reflected the match either.
“It’s always fine margins. In games earlier this year, we weren’t clinical in taking opportunities and that was the big difference this time. We took opportunities.”
There was, indeed, almost a freakish sense of every break hopping Leinster’s way, compounding their physical and tactical dominance from the opening moments, when they delivered a restart to Munster’s backline, not their pack.
As with three years ago, the opening restart held portents of what was to become a recurring theme of dominance from just one team.
Where did the performance come from? O’Driscoll’s assessment of the game’s mechanics were as precise as his team’s clinical execution of the basic requirements they needed to win the game.
“Games are won and lost at ruck-time, the speed of ball you create can stop and slow down your opposition’s ball. We managed to get some quick ball going forward and we managed to slow them down, which is exactly how we wanted it”
On a broader scale, Leinster’s motivation was as much internally generated — driven by intense frustration at being perennial European flops — rather than any insipid voices from outside their tent who had discarded the province’s chances.
“I don’t know,” mused Cullen.
“Leinster are traditionally a target of many people. I’m not too sure what that is about. We were happy with winning the league last year, but disappointed with our performances in Europe.
“Our home games? Fine, but we’ve been pretty poor on the road. So Europe is what we targeted this year the most.
“We were a bit messy in getting out of our group at times. In the quarters we had a scrappy win against Quins.
“We’re just trying to give ourselves a chance every week, trying to play to the best of our abilities and be a bit more dogged. There’s a lot of internal pressure in the group. Some boys have been around a while.
“Some of us are running out of chances — you run out of years in terms of being successful. We certainly all want to be successful and we’re really excited about being in the final and the prospect of winning a trophy for the second year in a row.”
And yet some of the Leinster supporters were clearly agitated to witness some of their heroes — Brian O’Driscoll and Cullen were notable exceptions, Michael Cheika had already scurried towards the sheds — partaking in a lap of honour afterwards.
There is an even more forbidding mountain to climb at Murrayfield against Leicester; complacency will be their biggest enemy.
“It’s something we’ll certainly watch out for,” warned Cullen.
“I’ve a Heineken Cup loser’s medal at home. It’s not something you bandy around the place and display with great pride.
“I want to win another trophy. We’ve got a couple of weeks to build into that game. Munster have been a great team, still are a great team.
“They’re the most successful in Europe, the ERC rankings show that they are way ahead of everyone else. They’ve a great bunch of players and fantastic work ethic. Leinster have always aspired to be as great as that.”