After seeing what the old guard could do in the first part of Scotland's summer tour, he has now turned to the youngsters to find out what the future holds for the national side.
Nowhere is that more true than in his choice of captain. Grant Gilchrist, aged 23, has never captained at professional level, has won only six caps (starting in four), and spent the RBS 6 Nations kicking his heels around the squad while the more experienced players did their stuff.
Despite all that, when Cotter was looking for somebody who could inspire the side while offering a bit of continuity from the first half of the tour, he had no hesitation in who to go for. "He has great leadership qualities and a pragmatic mind; he leads by example, which is important," was Cotter's explanation.
"It is a great opportunity for him. We are looking at how to move forward and he gives us an opportunity to explore options. He enlarges our profile and gives us another idea of where we are going. He has been here for three weeks, since the start, so though there have been a few changes, he will bring continuity with some of the ideas I want to put in place."
It is certainly a bold choice, though without the likes of Greig Laidlaw, Chris Cusiter, Al Kellock, Kelly Brown and the rest of the experienced captains, he was notably short of options. He did have the option of reverting to Ross Ford, who will become Scotland's most capped hooker, overtaking Gordon Bulloch, when he lines up tomorrow, but has opted for the future instead, pairing Gilchrist with 20-year-old Jonny Gray in the second row.
"They are players with a great potential," Cotter said. "Always in life, there are opportunities and this is an opportunity for both of them, one as captain and one as a very promising young player. They will be very keen to perform and I know they will perform against Argentina. It is exciting, exciting times."
Gilchrist himself was making a decent job of being calm and collected about the whole thing but even he admitted he had been shocked when soon after they arrived in Argentina, Cotter pulled him to one side and said: "keep it to yourself but I want you to lead the team at the weekend, how do you feel about that?"
The short answer was "amazed and honoured" but, once the shock had worn off, he took it in his stride. "It is something I am comfortable with," he said. "I captained the Under-19s and Under-20s a few times and it is something that does come naturally. There is not a lot that fazes me. I will go out and play my best.
"For me, this has been a good tour so far and the extra responsibility is something I hope to thrive on. When I have had leadership responsibility before, I have always looked at it as leading by example and trying to keep putting out the messages that we have had through the week and hope that we can stick to the game plan.
"I'm not going to be the tub-thumping breast-beating captain; leading by example sounds more like me. I like to play on the front foot anyway and put my hand up to carry the ball and take the team forward. If I can do that and the guys will follow me that is what I will look for."
What Cotter and his new captain agree on is their feeling of how close they came to getting it right in the last game against Canada. While they made far too many mistakes, they felt happy with the attacking shape and style, the number of chances they created and the aggression in defence. Keep those positives but actually deliver once they have done the hard work and they believe the rest will follow.
Which is one reason Cotter has tried as hard as he can to keep players from last week involved again, with Stuart Hogg, Sean Maitland and Peter Horne joining Gilchrist as the quartet who keep their starting places. Gordon Reid, who started last week drops to the bench to allow Alasdair Dickinson to start.
Grayson Hart, the scrum-half, has his first start after coming off the bench last week, as does Kieran Low, the London Irish back row who is shoehorned into the No.8 slot after all the other options became unavailable. "It is a bit new to me, but the skill set at No.6, where I usually play, and 8 are not that different, so I am reasonably confident," he said.
Blair Cowan, who made his first start against the USA but made way for Kelly Brown against Canada, is restored at openside flanker and in reality will probably share the No.8 workload with Low, his London Irish colleague.
Nick De Luca gets his wish of a chance to prove himself to the new regime with his first start since last season's autumn internationals, and Duncan Weir is handed the opportunity to grab back the starting position at fly half.