Basking in the glory of the 2011 World Cup victory, it was easy enough for Kaino to believe he could pootle about in Japan for two years, get rich and then come back for another charge at history in 2014. Maybe he still can. Blues coach Sir John Kirwan will be interested to meet when Kaino is here.
"Yes, of course," said Kirwan. "We would be interested in talking to him. He's a Bluesman and a great player."
The Highlanders, having lost Adam Thomson, are in the market for a bruising blindside, while the Crusaders, Hurricanes and Chiefs would probably all be interested in talking to Kaino.
But although interest is high, unlike Japan, money is an object. Kaino earns in excess of $1m in Japan and, despite being one of the highest paid All Blacks before he left, he'd have to return on a vastly reduced contract given the uncertainties about how much value he still has. He'd be lucky to be offered a quarter of his current deal.
It's that uncertainty about his ability that is the focal point of his decision-making. At 29, he's not old and his troublesome shoulder is finally coming right. But nor is he young either and, as he revealed to the Herald on Sunday late last year, he's stripped 8kg off his frame since shifting to Japan. He'd need that weight back to be effective in Super Rugby, for his power game to pack the same punch it did before he left.
A return to New Zealand would require him to complete a mountain of gym work and, even should he restore himself to the 109kg brick wall he used to be, the unknown will still be the unknown.
What effect will two years away from New Zealand have had on his overall game? Will he still have the same intensity, the same mental drive and hunger? Will he read the game as well? Will he carry the same impact in collisions? Will he scramble off the floor as quickly as he used to and make two tackles in the same phase?
It's tempting to believe that Kaino, unlucky not to be IRB Player of the Year in 2011, could still be the same destructive force after two years' absence. There's little evidence that it's possible. Rugby life in New Zealand is hard; the game is fast, training is tough, the skill levels are high, the intensity is relentless and it's a bit like the Auckland property ladder - it's a wretched business getting back on it, even for those who came off near the top.
Tamati Ellison managed to win an All Black recall last year after two seasons in Japan. In coming home a better player, he is the exception and, as much as he's impressed, he hasn't answered the critical question whether an established, world-class All Black can leave and then return pretty much the same player.
Inadvertently, Kaino could make himself a test case for generations to come. Increasing numbers of New Zealanders are heading to Japan and the likes of Kaino, Richard Kahui and Sonny Bill Williams have or had genuine thoughts of returning in time for the next World Cup. If Kaino commits to giving it a try and then proving it can actually be done, then expect to see increased numbers of All Blacks leaving after World Cups - convinced they will be back in time for the next one.