Who would have begrudged him a moment of reflection and to contextualise that, after all he's given, so much will be determined by what happens between now and October 31?
So did he take stock and remind himself what's on the line and that this is it for him - the last big push, as it were?
"Not really ... a little bit," he says. "I don't want to get caught up in that. The big thing about making decisions now is that you can start winding down and thinking this is the end of that ... this is the end of this...
"Leading up to the World Cup and then at the World Cup, I just want for it to be like any other year - to be really determined, to make sure you are at the peak of fitness, that you are working on your skills. Even if there is an end point, you want to be doing it right to the end ... we try not to let it be all about this being the last time.
"I think that would be unhealthy and that is a subconscious thing. I think in the back of your mind you understand that it might be. But I look at the Crusaders season, for example. Although the season was disappointing, in the last couple of weeks I had a smile on my face and I enjoyed it and I want to be able to enjoy what I do. That's how you approach it."
He, and more explicitly team-mate Brad Thorn, have made it clear they didn't particularly enjoy the last World Cup. The intensity was overbearing, the desire to succeed became all consuming and McCaw, in the final, was the climber hanging on to the rope for dear life, fearing his world would never be the same if he let go.
"A lot of us had been through 2007 so it was hard to enjoy 2011," says McCaw. "Enjoyment is a funny word. Satisfaction is the one thing you crave. When you are working hard and get the result that you want, it may not be that enjoyable to get there. But when you play against the Aussies and win the Bledisloe, that is when you are satisfied. You worked bloody hard and it might not be that enjoyable on the field at times to get the result you are after but after, there are times when you say I am satisfied the hard work is paying off.
"Going into the World Cup, the reward of being able to be the best team when it counts ... that's what keeps your drive going and what you take enjoyment out of. I know exactly what Brad was saying because I felt a little bit like that because you were on such a mission just to do it. That was one of the reasons we managed to get there. We have got to try to have the same sort of desire and attitude."
The All Blacks go to England as champions, which creates a new but similarly intense burden of expectation. They have never won a World Cup on foreign soil and no team has successfully defended the title.
It's not the external expectation that drives McCaw and his team-mates, though. They are conscious of it, know it's there, and know it can pervade deep into their lives if things go wrong. But to a man, they are predominantly driven by this desire to be continually better. The All Blacks are relentless in their quest to improve and no one more so than McCaw.
"I think it is the same for the other guys who are coming to the end that you want to finish off well," he says. "You don't want to peter out. I know that is a real driver for me. I want to be performing at my best and be the best out on the field. Then it takes away the pure winning and losing. If we aim to be better and give ourselves a chance, that's the bit that drives me and the bit that I think drives the team. It takes away that one thing at the end which is bloody important but it takes it back to the process and preparation.
"You have got to remember there is at least half the team or more who haven't been to a World Cup. So their excitement to try to get a piece of what we experienced is high. For us - who have - we have got to have the same sort of desire."
McCaw is also going to feel a little like a pilgrim in a savage land. Last year when the All Blacks played at Twickenham, his every act was jeered. Twickenham, somewhat archaically, still has the respective management teams sitting in the stands and All Blacks head coach Steve Hansen had an England fan - well-dressed, corporate-type - screaming in his face about McCaw for the full 80 minutes.
McCaw smiles, only fleetingly, at the memory. "I guess I understand it. I know that's the way it is," he says of his position as the man so many outside New Zealand want to hate.
If he could be bothered, he could rationalise the adverse reaction as confirmation he was by far the best player on the park that day. England, all puffed up and ready to make a big pre-World Cup statement, couldn't flip McCaw out of their pocket.
No matter what they tried, England were in the shadow of the All Black No 7. When they went wide, he was there foraging. When they charged up the middle, he was there tackling. When the All Blacks went up the middle, McCaw was there carrying. When they went wide, he was there recycling and scoring.
It was a performance that had significance both for what it confined to the past and projected to the future. Earlier in the year, McCaw had, for the first time in his career, experienced adverse commentary from his own public.
In the first two tests of the year against England, he was relatively quiet. A couple of mistakes made in full view, however, led to inevitable chatter that the skipper was on the wane, that time had finally caught up with him and the old master couldn't play like he used to.
McCaw admits he was troubled by that change in sentiment. "I think 12 months ago ... those [negative] voices started coming in and it does happen when you have a couple of games where you don't do things quite right.
"But it is easy to look at the things you do wrong instead of the things you do right and I think it is quite interesting. When you get over 30, people start picking on the same things you did wrong when you were 20 but blame it on you being old. The thing I have learned is that - obviously you don't want to make mistakes - but keep a bit of perspective on whether you are doing things any differently.
"If you do, you can get tense and anxious and caught up in that and it is not going to help you play. Especially over this year, I haven't been perfect by any stretch. Towards the end of Super Rugby, I was starting to relax a bit and started to think it's a lot easier when you are like that.
"You have to trust that guys like Steve [Hansen] will give you the facts. They will tell you what you need to be better and tell you when you are going all right. As long as you are listening to the right people, you will be fine.
"I always say walking off the field you have a gut feel about how much impact you have had. It's easy to look at tapes and justify things and say this and that wasn't your fault. You have to be careful about it and, conversely, you have to be careful that you don't watch the tape and think, 'oh, I wasn't that good'. You have that gut feel coming off and it's a real skill keeping that in balance which is why I back myself when I walk off to know that I had a good day or whether I wasn't quite there."
His gut feel should have told him he was superb at Twickenham last year. Just as his gut feel told him earlier last week as he surveyed the room, that in a few months, he and his team can return to the same ground and deliver the same quality of performance.
"I really do," he says when he's asked whether he thinks this All Black side can achieve all that they want. "We have gone over a few little things that we are going to add to our game and how we are going to get better.
"You can see the level of detail and everyone is really excited about it. You look around the room and there are obviously more players to come back in, but there are some pretty talented individuals. So if we get the right ball in the right spots and play the way we have designed to do, then it will be bloody exciting. If we can get that right, we are going to put teams under a hell of a lot of pressure."
