Maybe I'm the only one interested in this, but here's another look at penalty minute totals by conference and team. (Also see the 2008-09 post and the 2007-08 post on the same subject.)
Average penalty minutes per game, by conference
Any Canada West followers have any idea what's going on out west? There's a 30% drop in PIM in the last two years, and it's to the benefit of everyone but Alberta. Six of the seven teams have experienced a drop of between 19% and 38% in their penalty minutes, but the Bears are down just 13%.
It's not something I can explain in five seconds of thinking. They were already one of the least-penalized teams, so if the other coaches complained (say, two years ago) about unfair treatment for the U of A then you'd think the Bears would be whistled more often, not less, and that the other teams' penalty calls wouldn't change much.
Of course there could be another explanation. Fewer games going to overtime might explain some of that, but overtime doesn't add 30% to the game time. It could be because of a rule change, or unwritten rule change. Or it could be a statistical anomaly, which is likely in a sport where they often don't record shot totals correctly. (However, I do like Jason Wong's tongue-in-cheek suggestion that it's because refs no longer work on commission.)
Here are the most penalized teams in 2009-10, ranked by how much they "out-penaltied" their conference average.
Most penalized teams, 2009-10
The Stingers are the only team to appear on this list in the last two years, just like there was only one team on the overlap of the 2008-09 and 2007-08 lists. One explanation for that is coaches dealing with (i.e., shipping out or yelling at) high-penalty players in some way; another one is simple regression to the mean (a cruel, cruel mistress).
Least penalized teams, 2009-10
This list seems more consistent: Alberta's on there yet again, along with Lakehead and Queen's. Toronto and Acadia also show up in two years out of three.
How much of this carries over from year to year? Well, some of it does; teams that are less (or more) likely to take penalties tend to stay that way, but not as much as you'd think. It seems that teams regress maybe by about 60%, or three-fifths, back towards the conference average.
So a team like Acadia might not be 36% below the AUS in 2010-11, but maybe about 14% lower, assuming no change in roster or strategy from a year ago.
Let's look again at the extreme team, McGill.
Say the Redmen are going to be 9% higher than the OUA average this year (remember, regress three-fifths of the way), and that the league average is 20 PIM per game. That means McGill would be called for 1.8 additional minutes per game, or 50 extra minutes over the whole season.
Some of those minutes don't lead to powerplay time for the other team, but without looking up the exact percentage, let's say half of them do. That gives us about 25 minutes--i.e., 12 or 13 penalties. CIS teams have a 19% success rate on the powerplay, so we would expect McGill to yield about two or three more goals throughout the season, based solely on the extra penalties they take. As best as I can estimate, those goals are worth about half a win in a 28-game season.
Could the Redmen have used another half-win, or one point? Well, no, they were four points behind UQTR for first, so the gap can't be overcome solely by taking fewer penalties.
But as a quick guide, an undisciplined team that takes two more needless minor penalties in every game costs themselves about a point over the 28-game CIS season. (And that doesn't account for the extra fatigue suffered by the penalty kill unit, or by players double-shifting to replace whoever was sent off.)
Now, very few teams are that penalty-happy, but this exercise nicely illustrates the importance of not being stupid on the ice. Which every hockey fan knows instinctively.