New Zealand's recent dominance of Super Rugby has been put down to superior skill-sets.
That's part of the story, but as is becoming increasingly obvious as the 2018 competition plays out, what really sets the Kiwi teams apart is their greater collective rugby intelligence.
It's as simple as this – New Zealand's teams have collectively built their mental strength to the point where they have this inner belief in themselves, each other, their coaches, and their gameplan and consistently make better decisions and tidier executions than their South African, Australian, Argentinean and Japanese opponents.
It looks, when it plays out, that New Zealand's players are just that little bit more skilled and innovative, but those key moments of magic or accuracy only manifest as a result of the innate rugby intelligence that sits beneath.
It would be not quite right to say New Zealand's players are collectively smarter than their opponents, but it wouldn't be entirely wrong either.
Put another way, the chance of a South African or Australian player making a dumb decision under pressure is significantly higher than a Kiwi doing it.
The possibility of a South African or Australian team suddenly doubting themselves or drifting out of a game they once had control of is way higher than a Kiwi team doing the same thing.
It hasn't always been like this, but in the last few years, with the exception of the Blues, New Zealand's teams have been remarkably good at not playing dumb rugby.
There have been few, if any, memorably painful moments of individual or collective idiocy. Put Kiwi teams under pressure at the moment and they tend to respond well.
They hold their shape, work in unison and play with a clear-headed conviction that if they came into the game confident they were good enough to win, they should hold that thought for the full 80 minutes.
Which isn't true for the rest of the competition as it feels inevitable that there will be a period in any given game where non Kiwi teams will ditch the gameplan, lose their shape and effectively do themselves out of victory.
Look at the evidence so far this year. The Chiefs were in a bit of strife at half-time on Friday night against the Bulls.
They were 28-14 down and struggling to get their game going. They were teetering, vulnerable and if the Bulls had been able to score first after the break, that probably would have been game over.
But that's the thing, the Chiefs found a way to adapt and change their fate. They worked out they needed to be smarter on defence because the threat lay not with the power in the Bulls' backline, but the pace.
Everything changed in the second 40 minutes because the Chiefs had the ability to change tactically, react mentally and pick apart their opponent.
The fulltime score was 41-28 to the Chiefs and the Bulls, as promising as they had been and improved as they clearly are, can't yet say they have the breadth or depth of rugby intelligence or confidence that they need to regularly win at his level.
Even the Blues, against the odds and all predictions, suggested with their dramatic late win at Ellis Park, that they too, may, finally have developed the mental starch of their Kiwi peers.
Their talent has never been in question but their ability to use it wisely and effectively has.
One win against the Lions doesn't signal that all ills have been cured, but the composure the Blues showed to claw their way back from being 21-5 at an intimidating ground against a quality team, was remarkable.
They may not have turned the corner quite yet, but what they demonstrated in Johannesburg is that they at least have the potential to do so.