The four teams to have survived this far at the World Cup are vastly different in playing style, vision and philosophy.
Yet they are united in that they are all respectively governed by a head coach with a huge presence and a PhD in setting an agenda.
If this World Cup has taught us anything, it is surely that coaching now is all about the cult of personality and that when New Zealand Rugby's board come to appoint a new All Blacks head coach before the end of the year, they can't lose sight of that.
A job that was once about organising 15 blokes to run in the same direction has morphed into something entirely different in a professional age of mass media coverage, sponsor influence and free labour markets that have led to the global dissemination of rugby intelligence.
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The head coaching role is no longer the domain of the technical and tactical mastermind, operating in the shadows of the training ground, clad in tracksuit and commanding those around him with shrill blasts of the whistle.
A head coach is now a figurehead, a statesman, a near-genius in the art of psychological warfare. A head coach these days has to understand the difference between tactics and strategy and be conscious that they are employed to win wars, not battles.
They have to be an arch manipulator of referees, players and the media and while they don't need to be academically smart, they have to be street smart; cunning and with a deep insight into the flaws, frailties and limits of the human condition.
It is an exposed and lonely place. The head coach sits on the front-line, providing the biggest clues of all to where his side may be weak, where they might be strong and how they intend to attack the opposition on game night.
And perhaps it's no surprise that the last four teams standing are coached by men with combative instincts that have been used so well over the years that they have developed bigger profiles than most of the players.
Steve Hansen, Eddie Jones, Warren Gatland and Rassie Erasmus are the big four – the men who have come to see that a press conference is not a chore, but an opportunity to destabilise their opposition and potentially impact their preparation and performance.
They get that coaching is a job only for those with the mental strength to accept that their every decision, selection and utterance will create a narrative of some kind and they have to be ready to bend it in the direction they want.
Call it the ability to control the message, but it is really more than that. It's the ability to detect weakness in others and strategise a means to exploit it that may often require having to plan three to four moves ahead.
It's an art form because to be aggressive or provocative – to play what is universally known as mind games with a rival coach - is to invite a response that may prove to be destabilising for the initial aggressor.
The retaliation can potentially be the killer blow and so it takes a deep thinker to determine the potential advantages and disadvantages of verbally antagonising a rival coach.
But to not respond is to present weakness and so managing this battleground is now the guts of the job and that's the reason All Blacks coach Steve Hansen admitted on Tuesday that the whole business of mind games is not harmless theatre.
"It's a real thing, but sometimes you are better to not bother going there and sometimes you are," he said.
"Eddie [Jones, England coach] will decide whether he wants to go there and I have already decided what I am going to do so you will have to wait and see. There is no point is there, he's a smart man. I know him well and he knows me well."
Less than half an hour later, it became clear that Jones had decided to "go there". Holding his own press conference on the other side of Tokyo he was on a mission to paint the All Blacks as paranoid and rattled.
He mentioned that someone with a video camera had been spotted filming from an apartment overlooking England's training ground and was smart enough to know he didn't have to accuse the All Blacks as the media would do that of their own accord.
Knowing how successfully Hansen has created this idea that the World Cup is business as usual for the All Blacks who live with intense pressure all the time, Jones than tried to expose that as a myth.
"We don't have any pressure, mate," he said. "No one thinks we can win. There's 120 million Japanese people out there whose second team are the All Blacks.
"They [the All Blacks] have got to be thinking, they're looking for a third straight World Cup, so there will be pressure there.
"I don't think they're vulnerable but the pressure is real. The busiest guy for them will be Gilbert Enoka. They will be talking about it the whole week. It's potentially the last game for their greatest ever coach [Steve Hansen], and for their greatest ever captain [Kieran Read].
"We've been preparing for this game for two-and-a-half years. Even back then we knew that we would play New Zealand in the semi-finals. We believe we've built the game to take New Zealand."
Jones had diverted attention from his team. He changed the agenda to one that suited him and his players as it meant no one was asking questions about their ability to deal with pressure and readiness to win against a team they have only beaten once in their last 16 attempts.
Jones will be hoping for a response. Hansen has already suggested he doesn't want to engage in verbal battle and so to be drawn into a fight would be a little victory for Jones.
But the England coach is unlikely to get what he wants because much of Hansen's successful tenure has been built on knowing who to attack and why and who to leave alone.
He was happy to verbally spar with Ewen McKenzie because the former Wallabies coach rated himself in that area while Hansen didn't hold the same view.
McKenzie lacked the mental agility to think on his feet and lasted barely two years in the role. Hansen, with some deadly observations and public put-downs having caused much of the damage to his opponent's confidence and reputation.
His best came when McKenzie surprisingly picked Kurtley Beale at first-five for a Bledisloe Cup test and Hansen suggested it was a decision made not by the coach, but the then Australian Rugby Union who were paranoid that the soon-to-be off-contract utility back was going to flee overseas unless he felt wanted.
Michael Cheika was another on the list of obvious targets given his certainty to respond to any kind of provocation. It became clear early in Cheika's tenure that he was emotionally volatile and hence a massively negative impact on his own team when Hansen needled him.
One year Hansen decided to never use Cheika's name publicly but to only refer to him as the Australian coach. It sent Cheika into endless rants about not being respected.
But among many memorable barbs, the best came earlier this year when Hansen was at a corporate function and was asked, deliberately, by on-stage MC Ian Fraser, who is a former chief executive of TVNZ and close friend, what he thought about former Wallaby great Mark Ella saying that Mickey Mouse could coach the All Blacks.
Hansen said that the Disney character wouldn't be able to because he was already gainfully employed elsewhere: "They've got Mickey Mouse coaching Aussie".
Of course Hansen knew that despite there being no media at the function that the comment would get back to Cheika and the illusion of it looking like a genuine expose would only make its impact more powerful.
Gatland has not been a target per se, but he was during the Lions tour in 2017 as there was always this sense that under pressure he would look to protect himself rather than the team.
As the tour developed, Gatland made a series of increasingly bizarre decisions, one of which - calling-up six additional players based on their proximity to New Zealand rather than actually being deserving of selection - Hansen publicly predicted a few days before it was confirmed.
First Gatland had to worry there was a mole in his set-up and then he had bigger problems because the decision to bolster the squad with players who didn't deserve the jersey saw him incur the wrath of his own team as well as that of the wider Lions rugby fraternity.
Then, after a heavy first test loss, Gatland made a wild claim that the All Blacks had illegally targeted halfback Conor Murray in the hope they could injure him.
A few days out from the second test Gatland appeared on the verge of imploding – something the Herald picked up on and published a cartoon of Gatland dressed as a clown.
"We probably had him where we needed him and then the bloody Herald made a picture of him as a clown, which I didn't think was right, so I had to back off," Hansen revealed at the same event where he made the Mickey Mouse quip.
In contrast he has shied away from jousting with Erasmus and Jones, no doubt because he has deduced there is little to be gained as both are quick-witted, especially the latter, and capable of putting the pressure back on the All Blacks.
Likewise, he never went after Joe Schmidt, but said before the game with Ireland last year that the winner would be the real world number one.
When Ireland did win, he then bestowed that status on them and asked whether they would be able to cope with the pressure of being favourites. It was designed to lodge in Ireland's heads that they were now the hunted and the long game worked.
He thought four moves ahead as sure enough Ireland collapsed when they met the All Blacks in the World Cup quarter-final with captain Rory Best admitting as much.
"Everyone talks about the pressure that's on the All Blacks before quarter-finals but when you haven't won one and you feel you have a great coaching set-up and great group of players then maybe you put too much pressure on," he said.
"Maybe we have been looking at this for too long and been so focused on it that we forgot to win some of the little battles along the way over the last 12 months."
For Hansen, the key to winning the mind games is to never lose sight of the strategical objective.
"You have got to have an inner belief about what the purpose is otherwise you will get knocked off the bike pretty quick," he says.
"There are a lot of things that come at you and you have got to be thick-skinned as there is a lot of pressure and scrutiny that comes with the job. Depending on the team...some have more pressure than others."
That the last four coaches standing are himself, Jones, Gatland and Erasmus, does not particularly surprise Hansen.
He gets that strength of personality and the public conduct of the head coach is as important as accurate goal-kicking at this World Cup.
"Each of those coaches are different in their own way too and that is the beauty of the game," he says.
"It is like the CEO of business there is not one model fits all so you have got to do it the way that suits your own style and that is one of the first things I asked myself when the opportunity to be a head coach came up many years ago in other teams: I asked what kind of style did I want?"
Summarising Hansen's style is difficult. He's a complex mix of humour, astute insights, classic one-liners and at times, brutal honesty.
Sometimes he's been provocative and at others he's been compassionate, empathetic for the traditions of the game and the need for them to be collectively protected.
He's both confrontational and adversarial and while some have labelled him a control-freak, he's acutely aware of the difference between being controlling and being in control.
He's conscious that as head coach he has to be above the minutiae and trust the legions of technical coaches around him to work the detail, fuss around with the small print so he can have an unrestricted view of the big picture.
"It has changed massively in the short time, or long time, I have been here with the All Blacks," he says of his role.
"In the last eight years, I have found I am doing less and less coaching. I am empowering other people. I am doing a lot of strategic work and people management.
"Dealing with off-field issues a heck of a lot. A lot of it is about strategising and the selections and your planning.
"You are the helicopter over the top and you have got to understand every little bit of the puzzle, but you don't have time to coach every part of that.
"You have to have the confidence to trust and encourage those people who are coaching in those specialist areas and have the ability to interact and challenge and be challenged."
It is apparent that the All Blacks' next head coach needs to be skilled in the verbal combat zones and cognisant of the emotional and psychological war they will have to wage every week.
They need to have the force of personality to impose the All Blacks' will on whoever needs to have it imposed upon them and the emotional intelligence to read what strategy is required to best do it.