And just when we thought it couldn't get any better? Well, while beating the auld enemy was one thing, beating the one opponent whom Ireland have never beaten, the biggest name in the game, in almost a century of trying would be quite another. As one Irish player has suggested: "Ten times better."
That may be overstating it, just as it may be exaggerating the increased degree of difficulty. Nonetheless, while it would be better, it would also be harder.
Aside from facing visitors who are highly wound up and who have a far more proven winning mentality, you have to wonder about Ireland's state of health, physically and mentally, at the end of a punishing schedule.
Somehow the eve-of-match mood at the respective press conferences seemed to convey this. That a suddenly taciturn John Mitchell and Anton Oliver wanted to get their 9.0 a.m. briefing out of the way as quickly as possible was made abundantly clear at their hideaway base in the Fitzpatrick Killiney Castle Hotel.
When the questions soon ran dry, Oliver released a delighted "great" as he jumped out of his seat to join his team-mates on the coach to Lansdowne Road for a final run-out. He and an edgy Mitchell looked like they wanted to have raw Irish flesh served up to them then and there, preferably wrapped in green jerseys. Men on a mission, a mean mission.
By contrast, the Irish camp seemed comparatively subdued later in the morning. Possibly this was in part due to the doubt about Peter Stringer, whose ankle strain prompted Brian O'Brien and Warren Gatland to rate the influential scrumhalf no better than a 50-50 chance.
"We'll give him until as late as possible to make the cut," said O'Brien. Brian O'Meara has been called into the squad.
While Ireland have had more games together, the All Blacks will be playing their first game since September 1st. This may partly explain why Mitchell has gone for seven of the Canterbury pack and 10 of that side which won the NPC final two weeks ago. With the 20-year-old debutants, Aaron Mauger and Rod McCaw, surrounded by provincial team-mates, cohesion shouldn't be too much of a problem.
Besides which, a fifth Test in nine weeks - punctuated by four European weekends - has left a host of the home side carrying knocks: Girvan Dempsey, Denis Hickie, Brian O'Driscoll, Shane Horgan, David Humphreys, Malcolm O'Kelly, Eric Miller, Anthony Foley, David Wallace and now Stringer.
The odds on the back row and David Humphreys finishing the game must be small, while, collectively, by the end of the English game they were emotionally drained. One player just sat in the dressing-room crying his eyes out for 10 minutes. It's been a freakish itinerary caused by a freakish set of circumstances, leaving Ireland as overcooked as New Zealand are undercooked.
The All Blacks are still hurting over the decisive Tri-Nations defeat in Sydney and are also itching to make a fresh start under a new coach.
"Being on tour lessens the pressure," admits Oliver. "It's easier. There's no family pressure, you don't feel the weight of public expectation because you don't hear it."
The pressure is immense. One Kiwi journalist suggested to Oliver that the All Blacks must come away with a clean sheet.
"Well, I'd hate to think if we didn't. Let's not even go there," he added, after pausing to reflect on the consequence of losing even one match on tour.
Such pressures are negative, but there's no escaping them. And it is one of their motivational tools. As with the fear of defeat, the legacy they've inherited in that black jersey will have been hammered home. It's liable to be feisty.
Once again a key element of the blueprint for success will be a smart territorial game, to make the All Blacks turn, to then make tackles and apply pressure, contest an All Black lineout which has been an Achilles heel in the last couple of years, and take the three-pointers when they're on offer.
Of course it may be asking too much of a slightly flahed Ireland to make about double the tackle count. So there'll be a need to retain possession, to leaven a clever kicking game with the lightning-quick raids out wide which unhinged South Africa a year ago, to ruck as hard and low as the All Blacks are now doing with renewed purpose under Mitchell.
The All Blacks have always been the most streetwise in slowing down opposing ruck ball, and they have a specialist groundhog at the breakdown in the great white hope, Richard McCaw.
Four years ago the All Blacks came to Lansdowne Road and recorded a facile 63-15 win. Keith Wood drew some flak for an honest pre-match appraisal making Ireland a 25 to 1 chance, then scored a couple of tries before leaving the fray at half-time. Yesterday he was saying "we have a chance".
It's probably their best chance since '78, but the bookies look to be on the money again in making the All Blacks nine-point favourites. In any event, Ireland will give them a game, maybe a helluva game, and this would be a helluva scalp. Better than England. Possibly the best yet.