In an online discussion, someone suggested that perhaps special teams made a difference. I investigated this angle first. St. Louis took 8 more penalties than Minnesota, so of course that didn't help. Fortunately, though, that didn't burn St. Louis while they were short-handed. However, it did mean 16 fewer minutes--relative to Minnesota--of 5v5 time, which they controlled (as measured by shot attempt & scoring chance differential) in 5 out of 6 games. Overall, though, differences in special teams didn't appear to explain this unusual situation.
Did Dubnyk win the Series?
In games 1,3, & 5--games Minnesota won--St. Louis suffered in both shooting% and save%. In particular, in games 3 and 5, Dubnyk shut them out at 5v5. St. Louis did not lack in scoring chances as they were either tied or ahead in chances in each of these games. It seemed, then, like St. Louis had the scoring opportunities, but that Dubnyk closed the door. But I still wasn't satisfied with that explanation.
I wanted to see if Dubnyk was really the key factor, or was there something else going on. For that, I went deeper into each game to see if St. Louis' scoring chances in games 1,3, & 5 were "High Danger Zone" (i.e., the slot). Because if the Blues had relatively more shots in this area, then no question that Dubnyk was a major factor in the series.
Using the shot diagrams for 5v5 situations, I compared the number of High Danger Zone shots (S) and goals (G) in each game that Minnesota won.
Game 1: Blues = 4 S (1 G), Wild = 6 S (1 G)
Game 3: Blues = 0 S (0 G), Wild = 6 S (2 G)
Game 5: Blues = 5 S (0 G), Wild = 5 S (1 G)
Game 6: Blues = 4 S (1 G), Wild = 7 S (1 G)
Now the picture becomes clearer. In terms of the highest quality shots, the Wild out-shot the Blues 24 to 13. Moreover, the Wild outscored the Blues 5 to 2 from this area. Why were the Wild able to get more quality shots? Comparing blocked shots I think provides the answer.
The Wild's defense blocked shots like there was no tomorrow. The shot diagrams were so crowded with Bs (for blocked shots), that I was unable to count with any kind of accuracy. An overall number, though, tells the story. Over these 4 games at 5v5, the Wild blocked 74 shots to St. Louis' 39; almost a 2-to-1 ratio. This helps explain a lot. St. Louis had more shot attempts, even in the High Danger Zone, but because of Minnesota's blocking ability, they hampered the Blues from getting high quality shots. This makes Dubnyk's job easier. During the regular season, Dubnyk was letting in shots from the High Danger Zone at a 13.5% scoring rate (5th best in the league), thus the 2 goals on 13 shots was on par with his regular season.
Who were the primary shot blockers for Minnesota? I figured a few players might stand out, but as it turns out, it was a team effort. The defense, centers, and wingers all contribute. In these 4 winning games, among the defense, Spurgeon and Scandella lead with 8, Suter & Leopold with 7, Brodin had 6, and Dumba had 5. Among the centers, Coyle lead with 7, Parise was next at 5, and Brodziak had 3.
Defense and goaltending are important, but a team still needs to score goals. I won't note the High Danger Zone shots by the Wild, but I'll note who scored. They include Parise (2 G), Pominville (1 G), Niederrieter (1 G), and Zucker (1 G). Similar to the goal scoring, noting who took the shots also showed several different players. As with shot blocking being a team effort, so was the Wild's effort to create high quality shots. Now I don't know if St. Louis were a low shot-blocking team all season, but I think it's sufficient to argue that they didn't do enough of it against the Wild. Chicago will have to figure out how to overcome this blocking tendency, or they too might get thwarted of excellent scoring chances by the Wild.
Overall, although Dubnyk was solid (except for Game 4), he did not have to overachieve for Minnesota to win the series. The team in front of Dubnyk took care of shot quality at both ends of the ice by creating more High Danger Zone scoring opportunities and by limiting St. Louis' high quality chances through a team effort.