Former Kerry captain Dara Ó Cinnéide. Photo: Ray McManus / Sportsfile
That '02 breakthrough must have felt like Everest at the time: a first provincial title in seven years.
Today, Leinster is merely base camp. And that, according to friend and foe, is attributable in large part to their history-making No 1.
"It's a phenomenal run," says Coman Goggins, Dublin's captain for that distant Leinster success in 2002.
"And even in 2010, with no All-Ireland medals behind him and you've eight or nine years of an inter-county career, you're probably thinking, 'Where does this end for me?' But obviously he wasn't thinking like that, it was a case of keep trucking on . . . and all of a sudden then, success after success."
The hard part for everyone else is wondering when that cycle will end. Cluxton turns 39 on December 17.
Two days later, if form and favouritism hold firm, he will climb the steps of the Hogan for a record-equalling eighth All-Ireland SFC success.
It has been a strange and possibly disconcerting year for the five-in-a-row champions: an unexpected change of manager, the longest injury-enforced absence of Cluxton's Dublin career (missing the first five league rounds), an unprecedented sporting lockdown, all followed by the shock departure of Jack McCaffrey.
But according to former Kerry captain Dara Ó Cinnéide, they remain out in front and will continue to do so for as long as their elder statesman stays involved.
"Look, everything is exceptional about this year," says Ó Cinnéide.
"But it still doesn't change the fact that Dublin are the best team in the country.
"Dessie Farrell is in instead of Jim Gavin. Jack McCaffrey, the best player in the country probably, is gone. But, you know, they're just so solid.
"I don't think Dublin are going to change until Cluxton goes. It's the one thing of hope that you have down here (in Kerry).
"Yes, Evan Comerford is a brilliant goalie - but decision-making is the X-factor. Okay, we've seen Kerry and Mayo have done particularly well on Cluxton.
"But you talk about him before the game and you still don't know. He's going to react to the game he sees before him. And he's just so good at that.
"Until he goes - that changes Dublin definitely. Because as good and all as (Brian) Fenton is, as good and all as Ciarán Kilkenny is, we know what they'll bring to the game . . . teams have done it in the past, kept them quiet."
One watershed moment from last year's drawn final offers proof of Cluxton's ability to pivot in a "split second".
Facing an oppressive Kerry squeeze, he laser-guided a monster kick-out to the soaring Brian Howard, hogging the Hogan Stand touchline. Three passes later, McCaffrey was galloping through for a stunning goal.
"I'm sure Evan Comerford has that process as well. But to think it and to execute it - there's a lot of variables there," Ó Cinnéide stresses.
One that requires a cool head - and bravery too.
"He backs himself in those situations," says Goggins, "that the play he's trying to execute is going to come off for him. And more often than not it does."
Back when Cluxton joined the senior set-up in 2001, replacing injured first-choice Davy Byrne for his championship debut against Longford that May, the game was fundamentally different.
"I was corner-back - looking for a kick-out at that time was an alien concept," Goggins points out. "In 2002, Stephen Cluxton very much fitted the mode of what the 'keeper was - mill it out to the middle of the field, hopefully one of the midfielders will catch it."
Over time, ball retention via rapidly taken short kick-outs became a central facet of his game.
"He has always been ahead of the curve," Goggins adds, before citing another example from the early years of this endless Cluxton era.
"Stephen was kicking frees, '45s, every evening before training," he recounts. "And it was only in 2010-'11 that Pat (Gilroy) started utilising the value of that eight or ten years of work.
"It wasn't one of those things where it was something he had never done previously.
"He has always looked to, 'How do I go better than last year?' If you stand still, you get run over. He's always worked on his game."
And this "relentless pursuit of being better all the time" is what still sets him apart. Eighteen years on from that maiden Leinster senior championship medal.