Schmidt left with plenty to ponder after clean sweep
Japan 13 Ireland 35
In the Six Nations of 2016 Josh van der Flier announced himself, pretty much from the outer reaches of Planet Contender.
The following November Garry Ringrose's much-touted candidacy was at last endorsed. Around the same time we were introduced to Joey Carbery, Dan Leavy, Luke McGrath and John Ryan.
Then in the 2017 Championship Andrew Conway got a foot in the door. Add in another eight caps from this tour and, by any stretch, we are getting closer to the deep end of the player pool.
It's important to put this tour into perspective: it was against tier two opposition in two countries. In those circumstances you are supposed to win pulling up, even if the Lions, plus a few injuries, have relieved you of most of a starting team.
Which is not to say that players can't develop in that environment; rather you wouldn't be beating a path to your local bookmaker on the back of it.
The three-Test trip ended in a Tokyo hot-house, Ajinimoto Stadium, where the opening game of the 2019 World Cup will be staged. Chances are it won't be touching 30 degrees and 72% humidity then, but coping with those conditions from New Jersey to Shizuoka to Tokyo has been good for all concerned.
Being fit isn't a skill, but it's a critical tool of the trade. And clearly fitness coach Jason Cowman is doing something right. It looks like he has a willing audience, for the recurring theme of this tour has been the appetite for hard work.
Partly you suspect it's simply part of the modern make-up of rugby players, unlike the old days when touring was as much about what you could consume as how long you could play for.
And partly it's because of the competition for places, and the intolerance of coach Joe Schmidt for anything that looks like something he hasn't proscribed as part of the plan.
He looked happy enough here after five tries had been added to nine from the previous week and seven from week one. Seven were conceded.
"We got tested last time (2015 World Cup) very late in the piece when it matter most," he said, on the subject of expanding his options.
"You're going to have world-class players who are irreplaceable. But at the same time, the closer you can get that gap the better."
Schmidt maintains that November will be an open book, despite the fact that he will have any number of stories to include. He may well start then with Jack Conan, one of the seven who started all three games on tour. In the face of accurate, quick and aggressive Japanese defence in Tokyo, the No 8's 23 carries were pretty much all gainline breakers. He has had a great tour.
So has captain Rhys Ruddock. He's at a different point in his career, and perhaps on a different trajectory, but it's impossible to imagine any of the missing men doing a better job.
"Rhys did a fantastic job leading on the pitch but away from the pitch as well," Schmidt said. And he's right. With two-way translation turning every press conference into a marathon, Ruddock's body language never once let himself down.
"It's important to learn stuff like that," Schmidt added. "The depth of players is important but you also need depth of character. He really brought that to the job."
Of the younger crew, both new second-rows Kieran Treadwell and James Ryan looked like they have something to offer. Ryan had a terrific impact on Saturday off the bench when his teammates really needed that bit of go-forward.
"Just getting to know the differences in culture, some of the expectations around what you have to do off the pitch as much as anything," said Schmidt, alluding to what Ireland have learnt about Japan ahead of the 2019 World Cup here.
You'd imagine a few of the new caps here are nailed on for that World Cup experience. Certainly Jacob Stockdale has looked at home.
"You never know how selection's going to go - I just have to get back in pre-season and work my bum off and really go as hard as I can," he said.
"After my first few caps I really want to push on so come November I'll definitely be trying to push for a starting position."
He'll he one of a growing band looking to be a part of that gig.
Japan - R Noguchi; (R Yamanaka 68) A Yamada, K Matsushima, Y Tamura, K Fukuoka; J Ogura (R Matsuda ht), Y Nagare (F Tonaka 53); S Ishihara (K Inagake 49), Y Niwai (S Horie ht), T Asahara (T Watanabe ht), L Thompson, U Helu (K Yatabe 64), M Leitch, A Mafi, S Matsushashi (Y Tokunaga 68).
Ireland - A Conway; K Earls (T O'Halloran 55), G Ringrose (R Scannell 79), L Marshall, J Stockdale; P Jackson, K Marmion (J Cooney 73); C Healy (D Kilcoyne 61), J Tracy (N Scannell 51), J Ryan (A Porter 61), K Treadwell (J Ryan 51), D Toner, R Ruddock (capt, S Reidy 55-61 HIA), J Conan, J van der Flier (S Reidy 68).
Referee - JP Doyle (England).