It would take a considerable stretch of the imagination to mistake the handful of Scottish sports hacks who have gathered before him for a crack Waffen SS interrogation team, but the new Scotland coach has clearly decided that one indiscreet admission will earn him a lengthy spell in the torture chamber.
Which is not to accuse the 52-year-old New Zealander of being evasive, for his general demeanour is more suggestive of puzzlement that anyone should care what he thinks than anything more sinister. As he prepares to send a Test team out on an international pitch for the first time in his life, Cotter's attitude is that the actions of his players will speak far louder than the words of their coach - so why on earth should anyone care about what he says?
"I don't like talking about myself, to be honest," he suggests at one point. "I don't mind talking about technical things about the game, but I'm not happy talking about myself or other things like that. I don't want people to be interested in me, I want them to be interested in the team. They are far more important than what I do or what I am like."
It is a disingenuous tack. Cotter might be a newcomer to the international arena, but he has been around rugby long enough, and at a high enough level, to know that the thoughts and words of someone in his position will attract as much scrutiny as anything his players do on the pitch. And, while he might be more comfortable barking orders on the training ground, nobody whose coaching cv encompasses stints in the rugby goldfish bowls of Canterbury and Clermont Auvergne could seriously suggest that the job ends there.
Ironically enough, Cotter had a certain talent for flying below the radar in his own playing career, turning out for the Counties Manukau province in New Zealand before moving to France to do shifts for a succession of decent but not exactly high-flying clubs. Physically, he still has the build of a powerful loose forward, but it was his misfortune to grow up in a country where - and at a time when - such players were only marginally less common than sheep.
Raised on a North Island farm, Cotter saw plenty of the latter as well but his projection of himself as a bluff, country boy hardly squares with the reality of what he achieved at Clermont. Revered by supporters as the man who finally delivered a French Championship title to a club that had fallen at the final hurdle on 10 previous occasions, his greater feat might actually have been to rein in the power and expectations of Clermont's notoriously twitchy Michelin backers and generate the stability that allowed him to enjoy an unchallenged eight-year reign as head coach.
To thrive in that snake pit takes a certain grasp of strategy, so it will be fascinating to see if Cotter can pull off the same trick at Murrayfield and get his new employers dancing to his favourite tunes rather than the ones they would prefer to play. "Vern knows what he wants and is pretty good at getting it," said one of his former charges in France, although the player neglected to add that getting what you want can be a lot easier when you have the Clermont chequebook sitting in your desk drawer - a luxury he will not have in his new brief.
So why has he come to Scotland? "I enjoy challenges," Cotter explains. "I think there is potential within the group [of players]. The group can grow. There are some experienced players and there is a generation of players coming through who are eager to play well and do well for Scotland. That was one of the reasons behind it."
Cotter's appointment to the Scotland job last year was a messy business. Nobody seriously believes the claim from Murrayfield that it was always intended that he should turn up a year later - the suspicion being that the SRU expected him to be released early from his Clermont contract with little or no compensation paid - but that water is now well under the bridge. From now on, it is about what he can deliver.
We can probably discount the hubristic target of a World Cup victory in 2015 that was touted a couple of years ago. You can almost sense Cotter cringing when that goal is mentioned, but he deals with the question quite neatly.
"That was just an expression of intent," he suggests. "Everyone in Scotland would like Scotland to win the World Cup. We have to start down that road in developing our game.
"Enthusiasm is an important thing and I don't mind that. What I do firmly believe is that everyone in Scotland must be together. It is not big enough. We can't fight the whole world unless we are all together.
"Looking at it objectively, everyone will say that it would be nice to get to the quarter-finals. We have some tough teams in our group. We have a tough draw. I will answer that after the tournament."
Cotter might choose to reveal little of himself in public, but the players will certainly know him at the end of a summer programme which will take them from today's match with the USA to a meeting with Canada in a week's time and then on, improbably, to Argentina and South Africa. It is a ferocious schedule, but it is also an immersion exercise, a rugby equivalent of speed dating.
"That is the positive side of things," he says. "We get to have a look at everybody. There are players who were injured and can't make the tour and that means there are opportunities for others, which is exciting. Logistically, it is not the easiest tour, but at the end we should have some positive information."
At the end of it, he, his wife and three children will also settle into the house they have chosen for themselves in East Lothian. Having taken Clermont into the latter stages of the French Top 14 Championship and the Heinken Cup - they lost at the semi-final stage in both - these have been hectic times for Cotter, but he is not inclined to complain about his lot.
But then what? When the tour is behind him, how will he relax? His answer comes as no surprise.
"No disrespect, but I won't answer that," he says. "I don't want people to be interested in me, I want them to be interested in the team and what the team does. It is an old saying, but it generally works, that the team is far more important than what I do. I just don't want to go down that track."