When the All Blacks ran out at Twickenham on December 1 within three games of matching their record 23-match unbeaten sequence and, with only an 18-18 draw with Australia blotting their copybook, they were being touted as the best team of all time.
But in an afternoon that encapsulated the tantalising unpredictability and eternal appeal of international sport, they fell to their second-worst defeat, 38-21, against England.
A sweep of the International Rugby Board's awards - Steve Hansen was named best coach, Dan Carter best player and the All Blacks best team - will have been scant consolation for a team who bucked the trend of recent World Cup winners by kicking on and improving in the year after their success.
Hansen made sure his squad kept developing with the introduction of players who brought an extra dimension to an already superb side.
He blooded nine new players as he started the reconstruction of a side that would otherwise be dominated by players in their mid-30s by the time they defended their title in England in 2015.
Changes is the first-choice side saw Aaron Smith inject verve at scrum-half while fearsome winger Julian Savea's tally of 12 tries in nine Tests in his debut season tells its own story.
Their brand of rugby was a step up even from that which they displayed in last year's triumph on home soil, mixing all the physicality expected of the All Blacks with a ruthless exploitation of turnover ball and an explosiveness out wide that few teams were able to stop.
"This year they have shown they are one of the great sides," said their former captain Sean Fitzpatrick. "They are trying to play the perfect game. They want to take it to a new level."
Hansen was not drawn into the debate about where his side might stand in the all-time rankings.
"It's for other people to judge whether we are the greatest team or not - or if we are a great team," Hansen said after his team's 25th successive win over Wales.
Australia were unable to match their neighbours on a regular basis but they bow to nobody when it comes to resilience.
Ravaged by injuries and humiliated 33-6 by France, the Wallabies climbed off the canvas to end their season with a hat-trick of wins over England, Italy and Wales.
Stopping the New Zealand juggernaut via their June draw was also an impressive display a month after they had been whacked 31-8 by South Africa.
Heyneke Meyer's first year in charge of the Springboks produced a home series win over England and a November three-game European clean sweep in which they won every one of their lineout throws.
But they managed only two wins in the Championship and were held to a draw by Argentina amid criticism, hardly original, that their physical approach was one-dimensional.
After crying out for years for more meaningful competition, Argentina got their wish and performed creditably in their first year in the Championship, and they played twice as many matches in 2012 as they had in any previous non-World Cup year.
They grew into the competition, developing expansive rugby and losing only narrowly away to Australia.
Coach Santiago Phelan and his squad, always increasing in depth and quality, will have learned a lot to take into their second year, though they looked exhausted in their final November match in Dublin when they were thrashed 46-24.
New Zealand and Argentina's anti-climatic finales were as nothing, though, compared with Wales's precipitous fall.
Having followed up their run to the World Cup semi-finals with their third Six Nations grand slam in eight years, they lost their next seven games, including yet another to their Cardiff nemeses Samoa.
That defeat and the heartbreaking last-minute loss to Australia, their fourth of the year, had calamitous consequences because Wales dropped into the third tier of seeds for the 2015 World Cup in England, and subsequently into a group with Australia and the hosts.
Even getting out of the pool stage looks a big ask and should Wales get through in second place they would be likely to find South Africa and then potentially New Zealand in their way.
That seeding looked an unlikely scenario when the Welsh became top dogs in Europe in March. Opening the Six Nations with a narrow win in Ireland, they sandwiched home wins over Scotland and Italy around only their second Twickenham success in 22 years.
They finished off with a 16-9 Cardiff victory over France, gaining a modicum of revenge for their one-point World Cup semi-final loss.
England's solid Six Nations, in which they beat France and hammered Ireland to finish second, earned stand-in coach Stuart Lancaster the job on a permanent basis.
Assistant Graham Rowntree said Lancaster had "dragged English rugby out of the gutter" following the off-field antics and dull play that marked their 2011 World Cup campaign.
It was a strange year for Scotland, who finished bottom of the Six Nations after losing every game, beat Australia, Fiji and Samoa on their June tour then lost at home to the All Blacks, Springboks and Tonga.
That last defeat was the final straw for coach Andy Robinson, who resigned.
Coach Declan Kidney was predicted to be close to departing Ireland after five successive defeats, including a 60-0 June mauling by New Zealand. However, the demolition job on Argentina in their final November Test secured their World Cup seeding and, in debutant winger Craig Gilroy, they may have uncovered a gem.
Next year's main attraction is the British and Irish Lions' tour of Australia where fans will hope for something similar to 2001 when the series was effectively decided in the Wallabies' favour by Justin Harrison's lineout steal in the last minute of the final Test.
- Sports & Recreation