There's no doubt that the sabbatical concept has served New Zealand Rugby well.
Richie McCaw insists he wouldn't have made it to the 2015 World Cup if he hadn't sat out Super Rugby in 2013 and Ben Smith returned to being a world-class force in 2018 after missing the back half of the 2017 season.
Conrad Smith is another who regenerated himself after taking extended time out of the game and New Zealand's ground-breaking move to selectively grant their best players paid time off has been instrumental in not only retaining talent but also keeping the All Blacks a step ahead in the last decade.
The biggest enemy to performance is fatigue and New Zealand have been smart in the way they have fought against burning out their most influential players.
If the idea of New Zealand's best players being absent from work for months at a time was a hard sell at first – a concept that invited opprobrium and cynicism - most followers have come to appreciate the necessity and value of battered athletes having a break.
Prolonged rest gave McCaw at least another season as an All Black, as it did Conrad and Ben Smith and so from being a seemingly gimmicky idea that was potentially too heavily weighted in favour of the player, New Zealand's ability to offer contracts with a sabbatical clause has become the envy of the world.
But the sand has shifted under everyone's feet in the last six months and the definition of a sabbatical has been broadened to a near-farcical extent.
New Zealand Rugby is trying to sell the impending contract extensions of Beauden Barrett and Brodie Retallick as long-term deals that will have a pre-agreed sabbatical period.
While neither player has actually confirmed their intentions post-2019, it is believed they are both hoping to play in Japan in 2020 and then return to New Zealand in 2021, staying at least until the 2023 World Cup.
The attraction of Japan is that the 2019 club programme is being moved to avoid clashing with the World Cup so 2020 will present a one-time-only opportunity for players to fit two campaigns into one calendar year.
For Barrett and Retallick 2020 presents a life-changing financial opportunity and it seems that it is easier for NZR to swallow this reality if they sell it to themselves and the public as four-year contract extensions with a one-year sabbatical clause.
Sabbaticals are a universally accepted part of the contracting landscape so if a year of Barrett and Retallick making money in Japan can be sold under that banner it creates the illusion of this being business as usual.
But taking a contract to play in another country for a year is not a sabbatical.
The original sabbatical contract in New Zealand was offered to Daniel Carter in 2008 when he was already in advanced talks to play for Perpignan in France.
Rather than him leave for two years NZR scrambled a deal where they persuaded him to go to France for six months as a sanctioned component of a three-year contract extension.
When Carter damaged his Achilles after three games with Perpignan and didn't play again, it highlighted the problem with time off not being time off.
Carter had played a full season in New Zealand in 2008 to then head to France in December of that year without a break.
He was tired and therefore vulnerable to injury, which was much the same with Ma'a Nonu who played in Japan after the 2011 World Cup and returned to New Zealand in 2012 shattered and well off the pace.
It was at that point the penny dropped that it wasn't really a sabbatical when players opted to play offshore rather than use their break to rest and travel.
And yet here we are, about to be told that the sabbatical clause has once again kept two of the country's best players in New Zealand longer term.
But that's not really true.
What's happening is that Retallick and Barrett are going to be playing a lot of rugby for a different employer for a significant amount of time.
It's debatable whether condensing two seasons into one, albeit at a less intense level, will enhance their career-longevity or rejuvenate them mentally and physically.
In all probability a year in Japan will take as much out of them as a year in New Zealand would and if they sign deals to be absent in 2020, at what point will they be ready to play again in New Zealand?
They can't return from Japan in January 2021 and come straight back into Super Rugby.
If they do that they will break and most likely if Retallick and Barrett do go to Japan it will require them to miss all of 2020 plus much of Super Rugby in 2021.
Everyone can see that this is vastly different to McCaw sitting out the first six months of 2013 to rest a tired body and enthuse a beleaguered mind.
NZR are trying to suggest they have no alternative but to accept that this is the best of a number of bad scenarios: that if they didn't grant Retallick and Barrett sanctioned leave, they would lose them permanently.
Maybe so but isn't that kind of the point of contract negotiations?
If playing elsewhere for a period is so important to Barrett and Retallick then let them choose between that and being All Blacks.
Offer them the chance to have a non-playing sabbatical as part of a four-year deal to stay, but tell them that if they want a year in Japan then they can do it without an NZR contract waiting for them at the end of it.
Let the risk sit with the players – pull the safety net away and say there are no guarantees about a contract at the end of their Japanese stint.
NZR is trying to portray itself as a victim of market forces when it appears to be more a victim of its own decision-making.
A sabbatical in the true sense has value in preserving careers and endorsing NZR as an employer that cares.
Allowing players to make millions offshore with the certainty they can come home after a year and resume their test career seems like the first step on a slippery slope towards losing control.