It was all too easy to attribute the periodic difficulties the All Blacks encountered in various games to their lack of experience and volume of relatively new personnel.
But Hansen knows he can't buy into such superficial arguments and his side were frequently guilty of losing their discipline when they came under pressure. It wasn't swinging arms and high tackles - although that was the case with Sonny Bill Williams' red card against the British and Irish Lions - but poor decisions around the ruck, cynical acts of ball killing and needless offsides.
Those cards were costly - more to performance than results. It was only Williams' red card that contributed to a loss but the All Blacks had to scramble for long periods to avoid defeat in other games when they incurred cards. There were two tests when they were shown two cards and it's just not possible to build a commanding performance when there are only 14 men on the field for 60 minutes.
There was also another significant cost that may hurt them more this year than last - reputation. There's no doubt sides of yesteryear did plenty to justify the All Blacks' reputation as an uncompromising team who would do whatever it took to win. But since Hansen has taken over, and probably some time before, the All Blacks have set high standards and their expectation is that they will play within the laws.
They know the importance of being disciplined, not just because it gives them a better chance of winning, but also because their rivals are constantly looking for any tangible evidence to promote the All Blacks as either thugs or cheats.
Test football is not played just on the field these days, with coaches pushing premeditated agendas long before kickoff in the hope that referees form fixed ideas about what they should be looking out for.
Few coaches can resist the temptation to publicly question the legality of the All Blacks' work and when New Zealand top the ill-discipline list with nine cards, some individuals will see that as grounds for outlandish claims.
What will concern Hansen most is that if the All Blacks don't tidy up their act, they will be providing England and Ireland in particular, who they play back-to-back at the end of the year, with easy ammunition to fire some telling shots.
The Irish were left fuming the last time they played the All Blacks in 2016. Ireland had enjoyed a historic victory in Chicago and when the two sides met 14 days later in Dublin, the Irish felt the All Blacks came with a mindset to play them off the ball.
Two incidents in particular enraged the Irish - an accidental head clash between Sam Cane and midfielder Robbie Henshaw. and a high tackle by Malakai Fekitoa on Simon Zebo which earned the former a yellow card when a disciplinary hearing later ruled it was more deserving of a red.
What the All Blacks can be sure about is that Ireland will bring up 2016 ahead of their clash in 2018 and if the All Blacks have painted a picture of being wild and reckless in the interim, it will be an easy play to make them out as the bad guys.
And if the All Blacks don't shake that reputation, they might find that in their biggest games this year, the biggest decisions go against them.
Tier 1 card counts - 2017
New Zealand – 8 yellow cards, 1 red card
Argentina – 8 yellow cards, 1 red card
Australia – 7 yellow cards, 1 red card
France – 5 yellow cards, 0 red cards
Italy - 4 yellow cards, 0 red cards
Scotland - 4 yellow cards, 0 red cards
Ireland – 3 yellow cards, 0 red cards
Wales – 2 yellow cards, 0 red cards
South Africa – 1 yellow card, 1 red card
England – 1 yellow card, 0 red cards
