In 2012, it needed a late, and rare, Dan Carter pot for the All Blacks to triumph in Christchurch. If Johnny Sexton's mental strength had not failed him in the clutch with a makeable penalty goal, the 2013 Ireland side would surely have won an historic victory in Dublin. As it was, Ryan Crotty's last gasp try snatched the result.
Hansen may have seen the replay of the Under 20s' defeat to Ireland. If he has, he will know that a committed, physical and accurate side got in New Zealand's faces, tackled like demons, and played the right tactics. New Zealand, conversely, were out-thought, playing dry weather in the light rain and having a seemingly unshakeable belief that moving the ball with width, to where their strength lay, was going to win the day. That blinkered approach was costly, even though they scored four tries to three. It is no use saying that they would have won by plenty on a dry day.
Rugby calls for different approaches when the conditions dictate. Look at the All Blacks against Llanelli in 1989, where it was ball up the jumper stuff in a howling gale, or the 1983 test against the Lions at Athletic Park, where Dave Loveridge took the game by the scruff as the Wellington southerly rocked the Millard Stand.
That New Zealand Under 20 side oozed talent. All Blacks apprentice Jordie Barrett was at second five, while one of the stars of the tournament, Shaun Stevenson, scored a superb solo try on the wing. Barrett himself scored a try and kicked two conversions, while Malo Tuitama on the other wing ran in a brace. But New Zealand's lineout unravelled, they failed to combat Ireland's drives, and were far too loose with their passing and handling. The final margin of nine could have been more. They were well beaten.
The most talented side does not always win, but the smarter side invariably does. All Blacks, beware.