Bizarrely, the five-second ruck rule has done Weepu a world of good.
Written off as too fat, too slow and entirely ill-equipped to cope with the introduction of the fast-ruck law, Piri Weepu may be on the verge of a career rejuvenation.
Predictions that this will be his last tour of duty with the national side may have to be revised. Weepu is not ready to be listed as extinct or even considered endangered, although he will probably never escape the latter charge. Trust in Weepu is likely to remain fragile but, for the meantime, he deserves the benefit of the doubt.
He's arrived in Europe fitter than at any point since the World Cup. Something has got through to him. The coaches say it is them: "We gave him some pretty strong guidelines before we picked the team," said Steve Hansen last week. "He has met those, hence why we are seeing a sharper, fitter looking Piri."
Maybe, but the same messages have been delivered many times before and had little effect. The re-birth of Weepu is being driven by more fundamental and base motivations - his survival instinct has kicked in.
He's been on a previous exploit's ticket with the All Blacks all year - owing his place to memories of what he'd once been rather than what he was delivering.
That couldn't last indefinitely and certainly not beyond this tour. The arrival of Aaron Smith has opened everyone's eyes to what is possible when an aerobic halfback is in the mix; when the emphasis is almost exclusively confined to pass and run - sweeping the ball from the deck without hesitation.
Historically, that hasn't been Weepu's game, mainly because the aerobic component has precluded him from playing like that. But now there is no choice: the introduction of the new law that requires ruck ball to be cleared within five seconds has removed the luxury of assessment time for the halfback.
Weepu was the master of dalliance; a lifetime could pass before he ever would under the old laws. Hands on hips, surveying all he could see - that was Weepu. He, more than any other halfback in world rugby, prompted the IRB to usher in the five-second law.
There seemed a cruel irony in that the style of play preferred by Weepu, and the one for which he'd earned national recognition, was potentially going to serve his death notice as a test footballer.
A faster game would likely chase him out of business, especially with a host of ideally built young halfbacks ready to emerge. Tawera Kerr-Barlow and TJ Perenara are the leading two contenders with the capacity to play this brave new style and there are plenty more looming.
Maybe the Scotland test will still prove to be a false dawn but what it showed is that far from being incapable of this quicker style of rugby, it actually suits Weepu perfectly. He's had no choice but to get fit to play it and, when he's fit, he's able to utilise a portfolio of wider skills that are impressively useful. Surely no one can have missed the connection - Weepu's best rugby has come when he's been at his fittest. When he's on top of his conditioning, he plays more instinctively and more dangerously.
There's little doubt that the long delays in the past were less strategic and more about him dealing with his fatigue.
Now he's fit, now he has a raft of young pretenders wanting to take his place and now he has different rules - all of which necessitate and facilitate him getting to more rucks, getting his hands on the ball and doing something quickly. Without time to think, without being paralysed by the burden of choice, Weepu was superb against Scotland. He can't pass like Smith but he does see more holes, sees the game two phases ahead in a way the younger man doesn't yet.
"I thought Piri made the most of his opportunity what with Aaron having played the majority of the game time this year," said Dan Carter of his halfback's Murrayfield performance. "He has been working extremely hard behind the scenes and for him to go out and put in a performance like that was really pleasing.
"Aaron is really quick around these rucks but the experience of Piri ... that really showed and he picked his times when to have a go and his organisational skills were fantastic as well."
It's now not inconceivable, depending on how Smith fared overnight in Rome, that Weepu could be restored to the starting halfback role against Wales. His contribution in Edinburgh was significant and there is a sense that, after a huge year, Smith may be fading a little and be better suited to making an impact off the bench.
Whether that scenario plays out longer term depends entirely on Weepu's ability to make it through the summer in the same or improved shape. The off-season has been his nemesis in the past - the period where he regresses rather than advances athletically. He can't afford a relapse - not now his future is looking surprisingly bright.