"I have to try to adapt to how the games are being officiated now," he said of rugby's hard-line stance on high tackles. "We could throw our hands up and say they are marginal calls but it's the way the game is going now and anything close to the head is going to be ruled on.
"That's where I have to evolve and change my tackling technique. We're well under way with that. I've been trying to lower my tackle focus."
The players, even the enforcers, accept that the head is now sacrosanct. They are being coached to lower their sights.
This is a matter of technique and, thanks to Kaino's explanation, a matter of record. What is more difficult to assess is rugby's cultural shift.
You don't need to go far to find the extremist wing of the "good old days" brigade. There are YouTube channels dedicated to big hits, there are Facebook pages dedicated to the dark arts. They provide ample evidence that there remains an audience for foul play.
On one, there is a 1998 clip of England wing David Rees slipping out of a coathanger tackle from a French cover defender, only to stumble straight into an epic Philippe Carbonneau spear tackle. You watch it through the slits in your fingers as your hands cover your eyes, just like a teen watching Halloween for the first time, wondering how Rees managed to get up, let alone walk again.
The clip is a reminder of the places rugby cannot return to, yet the feedback is instructive.
"Aaaahhh back when rugby was rugby," wrote Ben Jackson. "And I bet he didn't get up and moan or sulk about it!" added Graham Day.
Perhaps nobody caught the mood of the times better than George Garrett: "My god the snowflakes would die of heart attacks watching this."
Players are bigger, faster and stronger than they have ever been. They are athletic marvels with skillsets to match but there is a core of rugby fans who watch every week because the threat of violence is never far from the surface. The more this threat is subdued, the more alienated they feel from the modern product.
This conflict between safety and sanitation is not rugby's alone to fight.
It is a battle the world's richest, most high-profile contact sports league, the National Football League, is waging - and possibly losing.
The NFL's chief medical officer, Dr Allen Sills, this week announced that there had been 291 reported cases of concussion last season compared with 250 in 2016. While part of that 16 per cent leap could possibly be attributed to better self-reporting, the NFL realises that technique, as well as culture, has to change.
"It's not okay to simply stand behind that [self-reporting] and say, 'Well, the numbers are going up because we're doing a better job'," Sills said. "To me, this is really a call to action, to see what we can do to drive it down."
Yet, for some, the thought of making the NFL safer is anathematic.
"What used to be considered a great tackle, a violent head-on [tackle] ... you used to see these tackles and it was incredible to watch, right?
"Now they tackle. 'Oh, head-on-head collision, 15 yards [penalty].' The whole game is all screwed up. Football has become soft ... football has become soft like our country has become soft."
That was the call from one disgruntled NFL fan, but he wasn't any old fan, he was the president of the United States, and while it's easy to dismiss the words as the end product of a feeble mind, you can be sure he speaks - albeit incoherently - for a large swathe of the population.
A huge part of the appeal of any contact sport is the visceral sensation the spectator feels at collision time.
Even from the comfort of the couch, it is not unusual to flinch when a five-eighth throws a hospital pass to his three-quarters and you know the ball is going to arrive about the same time as the defender.
After all, what is the point of contact sport if you're trying to minimise contact?
Rugby has faced, and passed, these tests before. When they realised parents didn't enjoy the sight of players charging into the tackle area with boots flying, while those prone on the ground emerged with, at the very least, a macabre road map of sprig marks, they quietly eliminated rucking.
When they realised too many front rowers were ending up in traction after breaking their necks, they structured scrums to prevent the sort of chaotic collapses that were doing the damage.
Now, the elephant lurking in the backline is the gelatinous mass that floats inside your skull.
Brain health is rugby's awkward present and uncertain future.
Evidence that concussions received in rugby can lead to serious cognitive difficulties later in life are impossible to ignore, even if questions remain over why some players will be affected and others not.
While this remains a source of conjecture, awareness over the dangers of head injuries has never been greater.
Just this week, this reporter was talking to a former All Black trialist who had enjoyed his most destructive years as a hard-running No8 in the seasons just before the sport turned professional in 1996.
He'd recently been to a reunion for a former provincial team of his.
He was most looking forward to catching up with his openside flanker from that era, an undersized tackling dervish.
It was a sobering experience.
His former teammate, not much more than 50, was a complete mess, incapable of focusing and unable to articulate thoughts into complete sentences.
"It was impossible to make a connection," he said.
The state of his teammate scared him.
And if it's scaring those who have played, who once gave barely a thought to personal safety, imagine what parents think when consciously or unconsciously guiding the recreational options of their precious children.
So rugby is doing what it's done before, which is to promote technical adjustments in the game to make it safer.
The players will quickly adapt.
The mindsets of those watching may take a little longer.
