Cullen banks on Leinster's form horses to topple Scarlets
Leinster continue to establish a benign democracy on the field by maintaining a ruthless dictatorship off it.
The culture of complacency that swept through this place last season has been transformed; then, reputations remained untouched and Leinster finished with nothing.
Now, nobody is immune.
Devin Toner has further to fall than most and the sky-scraping second-row has now found himself edged from his provincial starting line-up for a huge game, so soon after Joe Schmidt issued the same medicine during the Six Nations.
As Leo Cullen watched Saracens lift their second successive European title last weekend, and eyed the swathe of significant players who didn't even make the match-day 23, he and his brains trust spied enviously.
They saw what might have been but also what needs to be done.
And so a squad already denied the services of the multi-medalled Jamie Heaslip and Rob Kearney have made big calls, like preferring Adam Byrne ahead of Fergus McFadden and holding back Sean O'Brien. But Toner's exclusion tops the list.
Ostensibly, he picked up a knock after the loss in Ulster and didn't train much since then. But he is not injured. Like O'Brien, if he is fit enough to bench, he should be fit enough to start.
Leinster's future is predicated upon not holding on too tightly to their past. That is how champions are made. Form trumps all, and Toner's form is clearly not good enough for his coaches.
"If we had had a Champions Cup final, how would we spin into a six-day turnaround, for example?" said Cullen.
"You'd need to have that squad, and it's important - look at Saracens at the weekend and you see the footage of some of their players who aren't in their match-day 23, some of the quality internationals they have, and that's what we're up against.
"So that's what we're trying to build here towards, to have that level of depth. Some of the young guys who come in, some are in and around the 20-cap mark now but had less than you'd count on one hand at the start of the season.
"So I think it's really important that we're building in that direction and making it a competitive group so that when an experienced international comes back, they know they have to play well.
"If not, there's going to be someone snapping at their heels trying to get in the team and I think we're lucky that we had the opportunity to bring a lot of young guys through this season, and hopefully the club will be in a better place for it."
Winning this year's Guinness PRO12 will validate that process but Scarlets' collection of hungry groundhogs and avaricious three-quarters will test the history which states that no away side has ever prevailed in a semi-final.
Which is probably why Cullen and Co leaned towards a more mobile pack, a 6-2 split and a plethora of breakdown specialists rolling on and off to try to thwart the men in red.
The visitors have spoilers aplenty, including Scotland back-row John Barclay - proclaimed "the most penalised player in the northern hemisphere" by Cullen in a momentary deviation into sensationalism.
Rhys Ruddock, Cullen's captain for the night, refused to bend the knee, interjecting "I thought that was you!" "Not since I retired," smiled the coach.
The sides' recent meetings are relatively uninformative as so many leading players were marked absent on both occasions due to international commitments but both will seek to put as much width on the ball as conceivable.
Hence, both outfits will concentrate on that key breakdown area.
Back-row James Davies, restored to Wayne Pivac's side after returning from a shoulder injury since April, leads the turnover stats but, instead of matching him directly with Leinster's leading pilferer Dan Leavy, Cullen has opted for the equally distinguished Josh van der Flier.
"All the time you're looking for balance in the game and the opposition you're going to play," said Cullen.
"The form of guys, physically how they are, the stage of the season, what's going on in the rest of their lives.
"You are making those calls and assessments all the time. Josh has been a very steady performer for us, the same as the rest of those back-row guys.
"Dan has come in and done incredibly well and it's great to have that luxury. But we've got a strong group that will start and we want to have a strong group to finish as well.
"It's the impact that those guys coming off the bench will bring, Dan and Sean. I don't know where Josh lies in those stats. But he's very strong in that area.
"It is just about trying to get a balance. You make calls every week. Some you get right; some you don't."
Scarlets would have liked to have had more choices to make, with injury depriving them of their Lions hooker, Ken Owens, as well as second-row Jake Ball.
"We just need to make sure we've learned the lessons from the games where we haven't quite hit the right notes this year," added Cullen.
"We can also take confidence from when we do get things right that there is a lot of threats through the team."
His side have more and should be able to unfurl them.