With the glaring exceptions of the 2015 and 2019 World Cups where they fell victim to the curse of failing when it matters most, Schmidt's Ireland proved that cohesion of team can be an all-conquering quality.
Schmidt's Ireland took the biggest scalps and established themselves as favourites to win the 2019 World Cup not on a ticket of expansive, free-flowing expression but on one of relentless accuracy where conservatism trumped ambition.
What made Ireland so much greater than the sum of their individual parts was their attention to detail; their in-depth understanding of what they were trying to do and their discipline to adhere to a relatively basic strategic approach.
So too did Schmidt's realisation that World Rugby's insatiable desire to pick away at its own law book and referee by committee and video replay would be a phenomenal leveller. He recognised that collision and cleanout had higher currency skills than pass and catch.
The genius of Schmidt was the accuracy of his analysis in knowing that Ireland could become a world force by playing a game of attrition and advancing in inches, particularly if they also learned how to stop counter-attack exponents like the All Blacks from living off the mistakes of their opponents and stealing miles they hadn't earned.
To be renowned as the architect of low-risk, highly structured rugby is perhaps not the legacy Schmidt hoped for.
Pragmatism is not an easy sell to a New Zealand rugby public who are wedded to this idea the All Blacks have to be daring and innovative and play with the sort of imagination and ambition that suggests they see the game in a different dimension to the rest of the world.
But what should have become apparent in the past three years is that the house of glory the All Blacks are so determined to build, needs solid foundations.
The All Blacks, however it may look, are not short of innate rugby intelligence. They have highly tuned micro-skills across the board and they don't lack imagination in how to use the ball.
What they have lacked sporadically – too often to achieve their goal of world domination – is adeptness in the equally valuable if less refined art of building the momentum and space to allow the magic to happen.
There's a fascinating statistical exercise looking at how often the All Blacks score a try on the back of generating just three consecutive phases where they crossed the gainline and recycled the ball quickly. Fascinating because it reveals that the All Blacks score almost every time they manage to hit the magic mark of three successful, dominant phases.
Three phases is all they need to break down even the best defence. Schmidt's value is that he understands how the Northern Hemisphere sides and South Africa are so good at preventing the All Blacks from building that critical momentum.
He is going to be poacher turned game-keeper, helping the All Blacks learn attrition rugby both in practice and attitude.
Schmidt gets trench warfare – the psychology of it as much as anything else – and his attention to detail and ability to see how defensive structures operate should create the basis from which the All Blacks can build a more robust attacking machine to generate momentum against the best Northern Hemisphere sides.
What the All Blacks have shown in the past two years, maybe three, is that they know how to exploit space but don't always have the means, knowledge or discipline to go about creating it.
This is Schmidt's mission in essence: To instil within the All Blacks a means to play through or around the brick walls they so often encounter and equip them to be able to generate the all-important three phases of go-forward they need to bring their speed, athleticism and natural attacking gifts to life.
The All Blacks can't just be tonic and finely sliced lemon – they need a generous measure of gin and this is what Schmidt is bringing.
He's shown with Ireland that he can make not-a-lot go a long way. With the All Blacks, he has the chance to show he can help make a lot go a really long way.
