He's just not up to scratch - it's his inconsistency that's the problemMontembeault had a very good world championship a couple years back and Canada won that tournament. I think that definitely helped his case.
I think he's had some good runs this year but is currently struggling. I think the Habs overplayed him on the account of primeau being so poor. He was the most used goalie this year before dobes came up, and remains the 3rd most used goalie in the league even today.
The two guys above him are perennial workhorses in hellebyuck and vasilevsky.