Mostly judged to be behind Aaron Smith and TJ Perenara, his role in the All Blacks has been largely confined to third-choice halfback. It's a brief that comes with the same amount of training and travel - time away from kids and family - but less much reward in the form of game-time.
No doubt that lack of comparative opportunity at the highest level was a major factor in his decision to join French club La Rochelle at just 27; the peak of his career. He will be a brilliant acquisition, and leave a big hole.
Right now an argument could be made Kerr-Barlow is again outplaying Perenara - just as he did during the 2015 World Cup when his composure was preferred to back-up Smith for the knockout matches. Last week his calming presence at the base made a huge difference in the second half against the Barbarians too.
And while Mitchell Drummond will debut off the bench against the French XV in Lyon on Wednesday (NZT), the gap between the All Blacks' established No 9s and the next tier is, at this point, considerable.
This match, in which he opposes four future team-mates, could well be Kerr-Barlow's 28th and final for the All Blacks, with Smith and Perenara favoured for the last two tests in Edinburgh and Cardiff. He is the most experienced member of the Luke Whitelock-captained mid-week team, and will relish the chance to provide leadership.
"Potentially it could be my last match," Kerr-Barlow said after arriving in Lyon. "Never say never but for the near future that'll probably be the case.
"We're in a privileged position to be in the All Blacks. I've been fortunate to have one last go and be with a great group of mates. I never taken anything for granted so I cherish every moment.
"It's a different feeling when you don't have all the usual faces in there but we've got an excited bunch of young men preparing to play what is a test match for us."
Back in 2009, when he first made the pro ranks out of Hamilton Boys, Kerr-Barlow was rated so highly he became Waikato's youngest contracted player in history.
Like most halfbacks he is a true competitor; fighting and scraping for everything. He is also seriously tenacious, attempting to play on at Ellis Park three years ago after doing his ACL, MCL and tearing the hamstring off the bone.
Sometimes his abrasive approach lacks the spectacular plays Smith and Perenara tend to deliver, but Kerr-Barlow is rarely flustered. He can be relied on, and is probably the world's best defensive halfback. He marshalls troops and stalks the back of the ruck like the Queen's Guards.
And through his kicking game, he laid on a couple of brilliant tries this season.
French lessons started during Super Rugby but have since fallen away. It reflects Kerr-Barlow's desire to live in the now, leaving reflection on his New Zealand career for the end of this tour.
When he does depart, he may not be remembered as the most glamorous halfback.
But, for many, his absence could reveal his true value.
