Back in the day, when rugby was still amateur, All Blacks training could turn a bit Lord of the Flies if the top team and dirt-trackers were given a licence to go after each other.
The coaches didn’t mind if there were heavy-duty flare-ups. Testrugby is, after all, about the survival of the fittest, and a bit of free-for-all carnage among teammates wasn’t deemed a bad way for the All Blacks to get themselves ready for whatever the French or Springboks would be throwing at them.
Tempers edging out of control on the training ground was also deemed a good sign that competitive tension was building among players.
Coaches liked to see a bit of passion to be reassured everyone wanted the same thing - to be in the top team - and that everyone was being held accountable to produce the highest standards to get there.
According to coaches and players, the All Blacks wound the clock back last week in Bordeaux and for the first time at this tournament, set 15 against 15 and let the natural law of the jungle prevail to some extent.
Both assistant coaches Scott McLeod and Jason Ryan said they were required to step in to cool things down several times, while Brodie Retallick revealed that Shannon Frizell flattened Anton Lienert-Brown in the most uncompromising manner.
It was a tackle with enough ferocity to ensure that come the next stoppage, Retallick whacked Frizell on the back and said: “It’s good to have you back, Shannon.”
That Retallick enjoyed seeing a teammate bury a teammate was no surprise. He’s a notorious enforcer of the highest standards, a to-the-death competitor who believes that the All Blacks’ performances will be a product of their training ground environment.
He and Dane Coles are the two agitators; the two who will readily smack a teammate or spray them verbally to make a point about standards and expectations.
But this survival-of-the-fittest culture is not so easy for the All Blacks to uphold in the current climate, where there would be extreme nervousness in some quarters about seeing teammates taking lumps out of each other.
It’s also, for the younger players, a relatively alien concept to be asked to compete against each other with that sort of intensity.
Gen Z and Millennials didn’t endure the competitive savagery of an education through the 1980s and 1990s.
They have never known the old authoritarian regimes of learning by rote and preparing for exam-only determined grades.
They are programmed to collaborate with their peers, and so getting the right mix of competitive peer-to-pressure at this World Cup is one of the major challenges facing the All Blacks, and indeed, all teams.
Determining where the line sits between healthy competitive tension and letting things descend into Lord of the Flies will have a massive impact on how well prepared the All Blacks will be for their quarter-final clash, if and when it comes.
Knockout rugby is merciless. Just one mistake or one failure to meet the expected standards can cost a team their World Cup campaign, and training has to look and feel like the sort of hostile environment that awaits.
This was a mistake the All Blacks made in 2019. The notoriously driven and demanding former head coach, Sir Steve Hansen, who knew how to encourage peer pressure to hold his players accountable, says he didn’t generate enough edge among the squad ahead of their semifinal defeat to England.
Hansen was worried that captain Kieran Read wasn’t going to be passed fit to play and he feared that if he built the tension too much that week, it would demoralise the players.
The insipid performance the All Blacks produced in the semi may have reflected the tone of their training week.
But equally, so too is it relatively easy to take things too far and foster a culture where individuals undermine and belittle each other with no constructive element to it.
When Wales played Fiji earlier in the tournament, their first five Dan Biggar had a full-scale, epic, tantrum at the end of the first half.
He was upset with his teammate George North for not kicking the ball out, and while his rage made for a great show, it would have been hard for New Zealanders to accept that from an All Black.
Even 30 years ago when training could be relentlessly brutal, the competitive tension was dropped on match day and the All Blacks worked as one - unified in their purpose no matter what had happened at training.
To win this World Cup, the All Blacks will need a few more full-on training days where there is a bit of scuffling and scrapping, but not so many as it destroys harmony and becomes the norm.
Gregor Paul is one of New Zealand’s most respected rugby writers and columnists. He has won multiple awards for journalism and has written several books about sport.