Michel Therrien has done many dumb things in his NHL coaching career. Questionable overuse of mediocre players like David Desharnais, a failure to make tactical adjustments other than rearranging his line combinations and over-reliance on slowing veterans are chief among them. None of those obvious shortcomings have imperiled his position with his boss, Marc Bergevin.
In another city, with another GM (see Pittsburgh, 2009), Therrien likely would have been replaced after a season like last year's. In Montreal, under Bergevin, however, Therrien has the enviable safety net of the best goalie in the world saving the team from disaster on a regular basis, and thereby glossing over the coach's failures. It's fair to say, based on the Habs record with and without him, Price is Therrien's ticket to job security.
During the 10-0 dismantling of the Habs by the Columbus Blue Jackets, though, Therrien might have finally made a fatal error. Leaving Al Montoya in net for all ten Jackets goals humiliated the veteran goalie who obviously wasn't having a good night. While it's understandable for Therrien to want to give Price the night off and protect him from risking injury in what had become a meaningless game, Price had other ideas.
As the score mounted and became more and more embarrassing, Price got up half-way into the second period and went to the tunnel to stretch. And stretch. Nobody told him to do so, but, like everyone else watching Montoya's embarrassment, Price assumed Therrien would show mercy and replace the guy. Price, the real leader of the Canadiens, was frustrated and upset by the way things were going on the ice and he wanted to get in there to help stop the bleeding. When that didn't happen; when the coach left his goaltending partner to serve out the whole mortifying sixty minutes without relief, Price could not have been happy.
Whenever a team takes the kind of nosedive last year's Habs did, we say the coach has "lost the room," but Therrien managed to survive that because he had the "Price was injured" excuse to protect him. Now, with Price healthy and playing at the top of his game, Therrien has a bigger concern. When he threw Montoya under the bus, he risked losing Price's support. And if he loses Price, he really has lost the room.
Max Pacioretty may wear the "C," but Carey Price is this team's captain. While it's not in his nature to quit just because he dislikes the coach, his opinion will influence his teammates. After that embarrassment in Columbus, he can't be thinking happy thoughts about Therrien. And that may be the dumbest thing Therrien has ever done.