The way rugby is heading, with the continued flow of professional coaches and players from south to north, the global landscape will become increasingly competitive and deal the All Blacks more frequent defeats.
That's the view of Jared Payne, the Kiwi turned Irish international who is settling into his first full season as Ulster defence coach after his playing career was cut short by concussion which, 18 months on, still troubles him regularly.
"I still struggle a fair bit," Payne, 33, says. "I haven't been to the gym since god knows when and don't really do any exercise because I'm a bit worried that's going to flair the head up because I still get headaches every now and then throughout the week if I have a big day or I spend too much time in front of the computer it sets things off a bit.
"It's about balancing things and trying to limit the headaches. They are settling down slowly but they still definitely flair up a bit. Long days of travel still get me so it's a bit different but it is manageable which is good."
Payne's belief that the All Blacks will be knocked over more often in the coming years is not something New Zealand rugby supporters are conditioned to. But, at present, it is difficult to dispute.
Certainly evidence in November strongly suggested the north is fast improving as the World Cup approaches. And while that test window offers a mere snapshot, and Japan presents a vastly different beast, the long-term financial challenges the south faces in attempts to retain talent at all levels is not getting any easier.
Ensconced in Belfast, Northern Ireland, for the past eight years where he and fiancée Christina are raising sons Tyler (two-and-half) and Jake (one), Payne is well placed to assess north and south divide.
The former Blues, Crusaders, Chiefs, Irish and Lions utility who played his first and last match – on the 2017 Lions tour – at Waikato Stadium senses the stranglehold the All Blacks had over their rivals is diminishing.
"The All Blacks have done unbelievably well to be at the top for so long but it's the nature of all rugby – it's happening up here in club rugby with the so called weaker teams getting better and the teams at the top finding it harder to stay there.
"Eventually that flows into world rugby and it's going to be tough on the All Blacks. They're still an unbelievable team to do what they've done. A few losses brings an overreaction in New Zealand but it's going to happen more and more in the future.
"The All Blacks are going to keep leading the world and if they do lose a few each year it's not a big thing because the standard is getting better.
"There used to be a big gulf between the New Zealand, Australian and South African club teams and those up here but I think it's slowly evening out. There's a lot of good club teams up here that would challenge the best in the Southern Hemisphere any day of the week."
Payne attributes this changing dynamic to a widening knowledge pool created by the transferring of intellectual property from players and coaches, particularly those from New Zealand, when shifting abroad.
At the heart of these boom times for Irish rugby, both on the test and European club stage where Leinster reign, is player management. England and France lag behind centrally run models but Ireland, Scotland and Wales are all learning to ensure their best peak at the right times.
"Ireland are getting results and the players are feeling fresh and enjoying it.
"They're very lucky the way they're set up here because you do speak to a lot of other guys and they play a lot of rugby and it does take a toll on your body with injury. Sometimes it's impossible to get up mentally and physically every week for 35 weeks in a year.
"Ireland have a pretty good balance and other places are trying to get that. Hopefully in the next few years that balance may get tweaked and you'll see the standard go up again.
"If they get that player management side right it will get closer and closer. It's shown, too, with the results of the November test series.
"It's going to be tough for the All Blacks but they'll find ways to try stay ahead and other teams will try and chase them so it's going to be interesting over the next few years to see where things settle.
"I can't remember a World Cup being this open. If you make the top eight, she is anybody's game from there."
During his 20 tests (2014/17) for Ireland, Payne formed a close relationship with Joe Schmidt. So much so that as Payne made the transition into coaching early last year he savoured a watch-and-learn expedition on the national team's successful tour of Australia in June.
"He's incredibly detailed and he's got an incredible mind," Payne says of Schmidt. "He knows what he wants and what that looks like and he's very good at getting that out of the players.
"On top of that he's a nice guy. He'll come down hard on you and crack the whip at training but when you switch off you can have a laugh with him as well he's got that side too so he's got that balance.
"He's a very good coach and it's no surprise he's got that team going so well. He's got some good players but he's got them to buy into his vision and he works incredibly hard to drive those guys in the right direction.
"It's almost the perfect storm for him.
"The type of person Joe is he would go well with any team. You could give him Northland under 15s and he would probably make them a championship team in a couple of years."
Despite his headache hangovers, Payne holds no regrets from his playing days.
Emerging from Papamoa to first feature for Waikato and Northland, he never envisioned representing so many teams or finding a new home on the other side of the world.
"Concussion has come a long way since I started. When you see some of the stuff guys coming up did when I was young and how it is looked at now the focus has massively changed.
"At the start it's not something you think about but it's more at the forefront of peoples' thoughts now which is good because you don't want people to get lasting effects after rugby do you?
"We do take risks but at the end of the day you don't want it impacting the rest of your life so people are doing the right thing these days the way they are looking after people.
"If you told me when I decided to leave New Zealand I would represent Ulster and Ireland and be lucky enough to get a few games for the Lions I would have laughed at you and called you something funny and carried on with life. I'm over the moon with how it has worked out."
Payne faced the All Blacks twice for a 1-1 record. These days he diplomatically suggests he sits on the fence when Ireland challenge New Zealand but, as far as career highlights go, defeating his country of birth in 2016 ranks right up there.
"It was a whirlwind week. Going to Chicago and playing the All Blacks was a big buzz then everything that went on with the Cubs and having heaps of mates over and seeing the city in full party mode, it was surreal and then to top it off with that performance it was unreal.
"It was something you always want to happen but you never really expect a week to go that well. It's something now I look back on with huge pride. It was unbelievable to be involved with the first Irish team to beat the All Blacks."
Should his prediction prove correct, such results may soon be more common.