There are many conclusions one could make from the recent advanced stats explosion in hockey, but the power of puck possession is most frequently brought up. Several new statistics track that aspect of the game in various ways, and research has shown a powerful correlation between winning and those numbers.
Hockey may often be a highly complicated orchestration of elite athletes running at unbelievable speeds, but such a simple notion remains true: You need the puck more than your opponent to win regularly.
Reading the recent post from the fantastic Jen LC breaking down Corey Crawford, one could glean all sorts of information from her typically illuminating work, but then she came to her conclusion and it all started coming together:
"There is a very strong correlation in the team’s Shots Against Rate and Crawford’s overall Save Percentage as you can see in the graph above ... The lesson we can learn here is that as the team improves its shot suppression techniques, i.e. neutral zone play, forcing opponents to areas with a low rate of scoring success, forcing opponents to pass instead of shoot, forcing turnovers, etc., so improves Crawford’s Save Percentage and the team’s overall rate of success during the regular season and into the playoffs."
So, yeah, a goalie like Crawford is only as good as the defense in front of him. And more specifically, that's directly related to the volume of shots against. This doesn't just mean a goalie who sees more total shots gives up more total goals; the rate at which a goalie stops shots goes down when he's forced to fight off increasingly large numbers.
That gets us right back to puck possession, an idea that's so simple you almost don't want to believe the entire sport could hinge on it so greatly. In some ways, this feels like the emergence of on-base percentage in baseball in the early 2000s; fans don't know what to make of it because it's not pretty, but the executives know how much its contributing to winning. Eventually, everyone in the game embraced OBP as the important number that it is, and the same will happen in hockey with puck possession.
There are several things that go into the success of a goaltender, and the rate of shots against is merely one aspect of that. We're also only talking about one guy and four years of data, so I wouldn't go all in with this information just yet. But the numbers are there, and the logic is there -- it's increasingly hard to maintain high level performance over a larger volume of reps. Just look at scorers in the NBA, high volume shooters tend to shoot lower percentages. It's just hard to maintain certain levels of performance based on the workload being required of you.
So there's probably nothing Earth-shattered being said here, but it's going to be an ongoing theme during the season and cannot be emphasized enough. The numbers, in so many ways, reflect the importance of maintaining puck possession. Now we can see that impacts Corey, not just the goal-scorers.