Never thought I'd believe this theory...but something like a loss to Wales is exactly what this All Black team needs. More specifically, it's what the coaches and selectors need.
Another long season is taking a toll no doubt, but are the All Blacks limping toward the 2017 finish line or the World Cup? Maybe both.
You can smell the decay from here, as the rest of the world catches up to the All Blacks by standing still. They need a major jolt, the ones already delivered this year apparently not enough.
Two 2017 statements from All Blacks coach Steve Hansen are memorable, for the wrong reasons.
A bit of sabre rattling last month, during the enduring spat with Warren Gatland, involved the declaration "watch what happens" when unavailable players return.
Gone was that essential place coaches need to be, in the moment and totally confident in the resources available right now. Even with a bunch of players out, the All Blacks have the raw talent to win any test match including over Aussie players who had gone 0 for 22 against New Zealand in Super Rugby.
There are truly essential All Blacks unavailable, but not actually that many. Try Brodie Retallick and Ben Smith. Putting Izzy Dagg and Julian Savea on that list - as Hansen did -is disingenuous, especially when you can replace them with the likes of Waisake Naholo and Damian McKenzie.
Just as tellingly, Hansen - who has been a breath of fresh if gruff air - appeared to go in-house when analysing the ridiculously narrow win over Scotland on the weekend.
"Everyone back home was telling us how they were getting bored with us being dominant. Well, they'll have to go away and have a cup of tea...," he said, without identifying who "everyone" was.
This felt like an unidentified itch which Hansen wanted to scratch. Hansen appears distracted, defensive. Like his team.
It has been a fascinatingly bizarre season in a way, one lacking pattern, but going into the last test the All Blacks do not rate a pass mark after stuffing up the Lions series, losing to Australia, and struggling to string together emphatic halves and games.
The Scotland test was iconic, where opponents minus the All Blacks' individual talent ran like they were enjoying the game, creating angles which had the world champions befuddled.
A Scotland team deemed not good enough for even second-string Lions selection almost pulled of the great rugby shock, but for inexplicable handling errors. Faced with a bit of dash and verve, the All Blacks went sideways again.
They soaked up the pressure, just. They can hang on for victories, with excellent defence and well-timed decisions to give up penalties and commit yellow card offences. As to why though, who knows?
But Hansen's call for the public to accept a changing international landscape, implying that the All Blacks' task has got tougher, is a joke.
Australia, South Africa and France have fallen way below their peaks. Scotland are plucky but minus serious firepower. Wales are more of an unknown quantity, but hardly imposing.
Yes Ireland have terrific players, and are better coached than ever. They have changed, evolved, improved out of sight, without a doubt. England are rising to be a mighty force, but they have done that before.
But all in all, the All Blacks face a weak international scene, given where Australia and South Africa have got to domestically and internationally.
In contrast, the All Blacks are fuelled by a national obsession and a centrally controlled system whose main aim is to produce the best-possible national side, aided by schools which help steal brilliant Pacific Island talent.
I'm all for coaches telling it like it is but some of Hansen's talk should be seen as cheap when the All Blacks have stalled so alarmingly. There is always the chance, of course, that public utterances do not match private thoughts. But it's not looking that way.