But in the wake of the crushing 4-3 extra-time loss to the United States in the semifinals at the 2012 Olympics, Herdman knew he had to say something sooner than later. As he walked though the tunnels towards the dressing room at Old Trafford, Herdman told team psychiatrist Ceri Evans his plan.
"He said 'Look I think you're right. Let's script some things and make sure we get the message right, because you won't get another chance at this,'" Herdman recalled.
As they approached the dressing room, equipment manager Maeve Glass came out. She was crying.
"She said 'Look, you don't need to go in there, it's done ... Christine (captain Christine Sinclair) just spoke to the team in a way she's never spoke to them before.' And there wasn't a dry eye in the room."
Said goalie Erin McLeod: "I get emotional every time I think about the speech."
The team huddled up. "You could hear a pin drop," said McLeod. And Sinclair, who scored all three Canadian goals that night in a memorable performance, rallied her troops.
"I just remember sitting in the locker-room at Old Trafford," Sinclair recalled. "Just everyone was heartbroken, rightfully so. Myself included. After a couple of minutes, it sort of hit me that three days from now we're playing for a bronze medal. Just this feeling came over me that I had to say something to this team.
"And I told them I had never been more proud to be their teammate. That the end result didn't happen against the Americans but I've never been more proud to wear that shirt. And that if heading into London, somebody would have said 'You're going to be playing for a bronze medal,' we would have taken it in a heartbeat. And I'm not leaving London without one.
"I don't know. It just had to be said. Cool if it had an impact on people."
It's typically modest Sinclair, who avoids the spotlight as if it was toxic. She likes to reduce her leadership skills to little more than leading by example. But her post-game address at the Theatre of Dreams sparked the team.
The Canadian women picked themselves off the floor and went on to defeat France 1-0 for the bronze medal thanks to a Diana Matheson goal in stoppage time.
The medal came 13 months after Canada finished dead last at the 2011 World Cup.
Sinclair, who turns 32 on June 12, was 16 when she made her Canadian senior debut in March 2000. She has long been the face of Canadian soccer but prefers to stay under the radar.
She's no ranter, says Herdman. She leads in a very subtle way.
"And I think often the best leaders, they don't say much but when they speak, people listen. Because they don't say much.
"And Christine works like that. She always says 'My leadership is in what you see out on the pitch. I lead by example.' But she's more than that. And I think what she's developed in the time I've been there is knowing that her voice has a huge impact on this team and there are moments she has to step up."
In recent years, encouraged by Herdman, the intensely private Sinclair has opened herself to teammates. And by doing so, she has strengthened the ties that bind the team and become a true leader.
Like all teams, the Canadian women run the gamut. Herdman's squad has girlie girls, girls who like girls, tomboys and everything in between. But they are also family who live and play together for months on end.
Herdman has worked closely with Sinclair and a small group on the team on leadership, what it is and how it works. In Salt Lake, where Canada played the U.S. one month before the London Olympics, Herdman even had them research five female leaders and come back and tell the group who they could relate to and why.
"So they were trying to figure out what leadership was. And it came right down to this group of women had never been vulnerable enough to promote a layer of connection where people could trust them. There had always been a guard somewhere put up — 'You don't need to know this about me, I don't want you to know this about me.
"Christine. What is Christine. She's just this wonderful person who's a great footballer who scores goals for Canada. Really? Let's find out who the real Christine is, because once you do that Christine, that's when your players are going to connect. And if you're vulnerable, they're vulnerable. And when everyone's vulnerable, then you get a reality and a connection and an authenticity in your group.
"And Christine made herself vulnerable in front of the group for the first time in her whole career."
The team then went to Switzerland for a final pre-Games camp. Instead of having the team go "100 miles per hour," Herdman focused on "mind, body and spirit" to further the connections between players.
"When she does (speak), it really is very impactful," veteran fullback Rhian Wilkinson said of Sinclair. "She doesn't waste her words. She'll let other people take the lead in general but when something needs to be said, she's the first to say it. And that sort of really started probably before Switzerland but I think that is when we saw her as the amazing captain she is."
The Canadian team repeated that Swiss camp in Mexico prior to this World Cup.
Sinclair, who has 153 goals in 223 appearances, has long been the straw that stirs the Canadian women. Herdman has worked hard to return that favour.
He talks of the need to be 90 per-cent-plus. Giving 80 per cent is good, he says, but to win a World Cup at home you have to be in 90-per-cent-plus.
"They did at the Olympics," said Herdman.
"To get to that level is not easy. It's tough conversations, it's a bit of adversity as well. It's getting out of your comfort zone and being ready to push to another level."
Veteran goalie Karina LeBlanc says Sinclair lives there.
"She's doing that every single day. She's not cutting corners. She's not trying to cheat anybody. She's just trying to make those around her better. That's somebody who you want to have as your captain. That's somebody you want to play with ... I think she's the perfect leader for us and for this nation."
The 90-per-cent-plus concept is part of the Canadian team tournament culture, with Sinclair a key cog in the Herdman team wheel.
"My goal is that Christine drives her team to get the best out of themselves. Because when she did it last time, they got the best out of her."
Sinclair's teammates cite her humility as much as her talent. Many speak of her in near awe.
Playing with Sinclair is "my childhood dream every single day," says forward Jonelle Foligno.
"Just an inspiration to be with and play with," adds 17-year-old midfielder Jessie Fleming, who says she has to pull herself back every so often just to remind herself she is on the same field as Sinclair.
Canada, ranked eighth in the world, kicks off the Women's World Cup against No. 16 China on Saturday in Edmonton.
Follow @NeilMDavidson on Twitter