Gatland's ethos and unwavering belief elevate his players far above their natural station
Warren Gatland was always a man with a plan. From the outset of this, his final Six Nations, he was telling anyone who would listen that Wales would win the Grand Slam if they won in Paris on the opening night.
This turned out to be less a prediction, more of a spoiler.
Too few of us listened to him. At one gathering, a whole room audibly chuckled at this outlandish suggestion.
Even when Wales produced what was then the biggest comeback in Six Nations history to overturn a 16-0 half-time deficit against France, they were still not being taken seriously as contenders.
Yet Gatland's message was taken to heart by the only people who mattered: his players. He believed and so did they.
"I've got to have that belief in us, and if I can portray that on to the players in some small way, then hopefully they can believe it as well," he said on Saturday night.
If one word is to sum up Wales' campaign, it is belief. For large periods they have been under the pump - in the first halves against France and England, and the second against Scotland - but their faith in Gatland's methods, and in each other, has remained absolute.
Even with the game tearing itself apart at regional level, which has left many of Wales' leading players out of contract, their focus has never wavered. The contrast with England's mental frailty is striking.
Wales have been masters of manufacturing their own momentum, whether that has been Liam Williams taking a high ball, a Josh Navidi turnover or, most commonly, a collective defensive stand.
"It is crazy because, right from the start, he said if we beat France, we will go on and win the Grand Slam," said flanker Justin Tipuric. "To sum it up, he knows how to win - and that is him, really."
By becoming the first coach to win three Grand Slams, Gatland's genius is undisputed. Still, there are those seeking to denigrate Wales' Grand Slam by suggesting it was not stylish enough. Nonsense. It is all the more impressive an accomplishment precisely because they have been forced to do it the hard way.
While this is an exceptional team, it is not a vintage collection of individuals. Only three - Alun Wyn Jones, Jonathan Davies and Liam Williams - would be nailed-on starters in a Lions XV. The brilliance of Gatland and his coaching team has been to elevate certain players far above their natural station.
Take Wales' points-scorers against Ireland: centre Hadleigh Parkes and out-half Gareth Anscombe. Both came from New Zealand five years ago, Anscombe having been on the outer edges of All Blacks selection, Parkes not even on the radar.
It has taken a long time for Welsh fans to take Anscombe to their hearts, but on Saturday he would have been granted the freedom of Cardiff as he outplayed Johnny Sexton, kicking seven from seven goals.
"It hasn't always been easy for him, he's had to fight hard to earn that respect from the Welsh public," Gatland said. "There's always that debate over the No 10s. It does put extra pressure on players."
Parkes benefited from Anscombe's cute chip to score Wales' only try after 70 seconds and then showed an unexpected turn of pace to prevent Jacob Stockdale from scoring. It is no coincidence that his elevation to the Wales starting XV has coincided with their record 14-game winning run. He has been transformed into the finest inside-centre in the northern hemisphere.
Where Gatland has been fortunate is inheriting a leader in Jones who is the heart, soul and lungs of Welsh rugby. With the game won and those in the stands celebrating, it was Jones in his 134th international appearance who was commanding the defensive resistance, even leading the charge-down attempt of Jack Carty's conversion of Jordan Larmour's try.
It is impossible to imagine Gatland enjoying the success that he has without Jones as his first lieutenant.
"What he does for the Ospreys, what he's done for Wales, he has to go down as one of the greats," Parkes said. "He's the leader, the one you look to, he's the one who steps up week in, week out. Every game he puts in a performance.
"He is a very nice man as well; a humble man. But what a leader, what a captain. What a bloke. He's special and he is key to this team."
It was Jones who immediately changed the focus of Wales' achievement by saying they now have a "target on their back" heading to the World Cup.
Other teams will be able to call upon greater talent and deeper resources in Japan, but no other team will be able to beat Wales' levels of conviction.
Whatever prediction Gatland cares to make needs to be taken seriously. (© Daily Telegraph, London)
Coming Soon: Independent.ie's new GAA newsletter. Sign up here