What he's able to do to influence tests is astonishing.
He is miraculous under the high ball - probably the best offensive chaser there is, capable of retrieving possession from almost any contestable kick.
He has smart footwork, astute timing, reads the game superbly and makes sure that he somehow does something to improve the position of his side if he has the ball.
It doesn't seem to matter whether he plays at fullback or wing, Smith sharpens the All Blacks attack.
He makes it better, he adds value.
That's a huge skill and not one many players offer. What Smith does is make sure that not much becomes quite a lot in an attacking sense.
He's the master at converting a quarter opportunity into a half-chance and making the seemingly impossible become the possible.
It's almost overwhelming to look back over the last five years and assess his influence and his teammates know it.
"He's a world class player," said All Blacks centre Ryan Crotty of Smith.
"He's one of the best, if not the best, outside back in the world. He's going to be a loss and as much as he contributes on the field he does as much off it. He's a real leader in this team and a good man."
The question for the All Blacks will be what can they do to ensure they don't overly miss Smith's influence for the rest of this year?
The onus for that will sit largely with Israel Dagg who is as close to a like-for-like replacement as the All Blacks could hope for.
The selectors are prone to springing the odd surprise but one probable scenario is that there won't be any change to the All Blacks starting back three this week.
Dagg, who has had a heavy workload and was struggling with a stiff knee in Sydney, may be given another week off.
Another week off may benefit Dagg, who will most likely become a regular on the right wing once Smith disappears.
His job will be to play that same steadying hand - to chase and retrieve kicks, to be brave in the air on defence and to guide his fellow outside backs through the game.
He will be asked to make things happen by using his experience and awareness to both create and finish.
The expectation is that Damian McKenzie will most likely be given an extended run at fullback and would benefit greatly from having a man of Dagg's experience on the field with him.