This World Cup serves to remind us that previous form or results counts for little. The fact that Ireland had won two of their previous encounters against New Zealand only handed Steve Hansen and his coaching staff a template to beat us when it mattered most.
The fact that Ireland had stuck rigidly to the same approach that delivered those two victories appeared to aid their cause.
In the build-up to this semi-final, a number of the Welsh players have been at pains to point out that they have won the last four encounters with South Africa and that the experience gained from those successes has strengthened their belief to deliver once again.
All well and good but I’d venture that this is an entirely different Springbok beast lying in wait.
Former Munster coach Rassie Erasmus has transformed the South African squad since returning from his brief sojourn in Ireland and has used the experience gained in European rugby to the benefit of his homeland.
The fact that Wales are contesting their third World Cup semi-final, having previously made the last four in 1987 and 2011, doesn’t sit well with us here in Ireland given the dominance our provinces have enjoyed over the Welsh districts, domestically and in Europe, for years now.
Warren Gatland, now coming to the end of a remarkable 12-year stint at the helm of Welsh rugby, has made light of those failings by organising and energising his players once they don that coveted Welsh jersey. In reaching the last four once again, he has maximised the talent at his disposal.
Wales played poorly for long tracts of their quarter-final against France and, in all probability, would have lost had Sebastian Vahaamahina not had his moment of madness.
That’s two games in a row now where his crass stupidity — remember his long looping pass that was plucked from the skies by George North that enabled Wales win the opening game of this season’s Six Nations in Paris, when the French, once again, blew a game they should have won.
Wales recovered from that poor opening performance to win a Grand Slam. The question now is, can they pick themselves up again from what Gatland accepted during the week was a very poor display for the majority of that quarter final.
What Wales did show last time out was a willingness to stay in the fight when things are going against them and a composure to stick to the task at hand.
It was no different in their key pool head to head against Australia, when they saw an 18-point lead whittled down to just one before replacement out-half Rhys Patchell delivered a clutch penalty kick with eight minutes to go to force the Wallabies into chasing a try.
The famed Welsh defensive machine delivered big time in closing out that game, in very demanding conditions, when their impressive fitness levels also shone through.
Those key aspects, rock solid defence and superb conditioning, have always been two of the main foundation stones of any side under Gatland, going back to the gruelling sessions he had the Irish squad endure in his time in the famous Spala cryotherapy chambers in Poland.
Fitness and solidity in defence, while vitally important against South Africa tomorrow, are unlikely to be sufficient for Wales to make a historic first ever final appearance.
Their set-piece will have to find a way to stand up to the relentless pummeling it is about to endure.
With Erasmus sticking to his formula of having a 6/2 split between forwards and backs on the bench, the Welsh pack face a brutal examination of their strength in depth.
From that perspective, the loss of one of their most consistent forwards, Josh Navidi, to injury in the back row is a cruel blow, especially as they have been without Taulipe Faletau all tournament.
South Africa ground Japan into submission up front, with their scrum and lineout maul wreaking havoc. Gatland is going to have to find a way to counter that.
The problem he faces is that, when Erasmus replaces his entire front five of Mtawarira, Mbonambi, Malherbe, Etzebeth and De Jager, he will be unleashing even bigger and better beasts in Kitshoff, Marx, Koch, Snyman and Mostert.
The back-up Welsh front row of Elliot Dee, Rhys Carrie and Dillon Lewis carry nothing like the power and impact of the Springbok replacements and that will leave them exposed entering the final quarter when the game will be decided.
South Africa were so intent on strangling the life out of Japan up front last weekend, they ignored the creative brilliance and razor sharp finishing of their two outstanding wingers in Cheslin Kolbe (below) and Makazole Mapimpi, who still scored two tries off a morsel of possession.
The news that Kolbe has been ruled out with an ankle injury is a major blow to South Africa but it has been diluted somewhat by the fact that Welsh full-back Liam Williams is also ruled out.
He has enjoyed a brilliant tournament. While his replacement Leigh Halfpenny offers an additional place-kicking option if required, he doesn’t carry anything like the same attacking threat.
South Africa have a very competent offloading game but don’t always appear to trust it in the bigger matches. To win a World Cup they will have to offer more than just brute force so it will be interesting to see what mix they bring to their game tomorrow.
Wales have achieved great success this year by stopping other teams from playing through the excellence of the Shaun Edwards inspired defensive model but, no different to their opponents, they will have to show a bit more scoring power.
In that respect, the return of Jonathan Davies to their midfield is a massive boost.
He was sorely missed against France and his recovery is about the only bit of good news Gatland has enjoyed all week.
To have any chance of winning this one, Wales must find more attacking intent and survive the physical onslaught. It’s a tall order but, if anyone can find a way, Gatland can.