Henry said it was an important fixture for them with a quarter-final looming, which will likely be against Argentina.
"We are just trying to make sure that the backbone of the team is ticking over all the time and guys who need football get an opportunity," the veteran coach said.
"Because we just don't know what's going to happen on the injury front going forward and who is going to be required for finals football. So we are just trying to do both of those things."
But a few questions remain.
Firstly, why was Victor Vito even included in the 30-man squad if the selectors would prefer to use lock Anthony Boric as loose forward cover in a game against Canada?
Also, why has Israel Dagg been named on the wing for the Canada match after Henry mentioned previously that they viewed him primarily as a fullback?
And, of the 22 to play this weekend, who is the openside flanker cover if McCaw gets injured?
Henry, who will celebrate his 100th game in charge of the All Blacks this weekend, didn't elaborate extensively on Vito but said Sam Whitelock or Boric would cover blindside flanker if there were injuries which prompted a re-shuffle.
"We think Sam Whitelock's got real ability as a loose forward/lock. He's played quite a bit there; athletic, got a big ticker. He can run all day and he's got good skill. So we would probably see Sam as the guy who moves from lock to blindside with AB going to lock. Although Anthony Boric has played [at number] six early in his career."
As for why veteran Mils Muliaina has been named at fullback with Dagg on the wing, Henry said: "We just think he [Dagg] needs another game and the other fella [Muliaina] needs to play as well and we think that's the best way of playing them, simple as that.
"He's part of this group, he's been an outstanding player and he needs to play. If he plays an outstanding game the thing opens up again doesn't it.
"Israel's been playing well, he got player of the day last week and played exceptionally well, which is pleasing ... it's a major challenge for both of them and that's good for the team."
McCaw's back-up, if he was to go down, would likely take the form of a 1.96m American Samoan-born tackling machine.
"Jerome Kaino could do that. I don't think that's an issue really.
"If Reado's not going to play 80 that puts some pressure on the other loosies to play 80."
On the 100-test milestone, Henry said the praise shouldn't be heaped just upon himself.
"It's a privilege to be part of that. It's special and I'm proud of that. To do that 100 times is also special, but it might be a sign of madness as well," he said.
"I didn't think I'd be reappointed in 2007 and that was probably 50 test matches ago, but I think it's a sign this group of people have done a good job. It's not all about me - I've been fortunate to work with some outstanding individuals.
"If I mention one I'm going to have to mention 20. I think it's a reflection on what the management team and the leaders in the team have done over those eight years to keep me in a job."
The former Wales' coach also singled out one person who had been there for him the whole time - his wife, Raewyn.
"She's been outstanding and you can't do these things unless you have huge support and she's been fabulous, so I can mention her."
It still remains unclear who the preferred halfback is, with Jimmy Cowan given a chance this week and he'll play his 50th test match.
Blockbusting back Sonny Bill Williams also gets a start in his preferred No 12 jersey, with Ma'a Nonu given a rest.
The game won't be a tight contest and for all the muster Canada have shown at the World Cup the All Blacks will possess far too much class.
