If we look at pre-lockout and trapezoid I think it is very fair to say he prevented around 4 shots a game. Since Brodeur did not give up many goals in those seasons this would have a huge effect on his save %. Let's look at '97-'98 and Brodeur vs. Dunham.
Shots Allowed Per Game:
Brodeur: 22.8 shots allowed per game
Dunham: 26 shots allowed per game
Now when you factor in quality of opponents. Dunham faced below league average competition in his starts (78 points per game) yet allowed more shots per game. If the Devils were so stingy then you'd think they'd tighten up with their back up in net.
If we pro-rate Brodeur's save % with the added 4 shots a game that would leave him with 1788 shots against and a new save % of .927 (instead of .917). If we do this with the following 6 seasons it is around a .01 increase in save %. I don't think it would put the Devils as a below average defensive team either.
When you look at post-lockout New Jersey. It is fair to say they were in fact a below average defensive team (especially when you look at the names on defense). From '05-'08 they averaged an SRS of about 0. Meaning they were incredibly average. Brodeur's shot prevention made their defense look stronger than it was. I don't think it's unreasonable to say he prevents about 1-3 shots per game depending on replacement.
You also don't take into consideration face-offs and flow of the game I know the TCG is working on a study which better exemplifies this and I'm interesting to see where it leads. Brodeur tilted the ice to the opposition side allowing the Devils to have more shots for and against. If you look at when Hasek's teams shots for are close to or above their shots against, his save % drops.
I've compiled the numbers for Brodeur's shots against vs his backups' shots against, year by year, from hockey-reference.com. Here they are.
Year | Brodeur | Backups | Diff
1994 | 28.3 | 29.1 | -0.8
1995 | 24.9 | 25.3 | -0.3
1996 | 26.4 | 23.4 | 3.0
1997 | 25.5 | 27.1 | -1.6
1998 | 22.8 | 26.0 | -3.2
1999 | 24.5 | 24.3 | 0.2
2000 | 25.0 | 27.6 | -2.6
2001 | 24.6 | 22.5 | 2.1
2002 | 22.8 | 23.2 | -0.3
2003 | 23.4 | 21.8 | 1.6
2004 | 24.3 | 21.5 | 2.8
2006 | 28.9 | 28.2 | 0.7
2007 | 27.9 | 28.3 | -0.5
2008 | 27.0 | 28.0 | -0.9
2009 | 28.8 | 29.3 | -0.5
2010 | 26.6 | 28.3 | -1.7
I would not put too much weight on the results from any single year, save perhaps 1994 or 2009, because of sample size issues. I calculated a weighted average of the difference from each year. Here are the results.
Estimated impact of Martin Brodeur's puckhandling: -0.60 shots per game.
Estimated impact of Martin Brodeur's puckhandling (pre-lockout): -0.67 shots per game.
Estimated impact of Martin Brodeur's puckhandling (post-lockout): -0.39 shots per game.
A critique frequently leveled at this approach is that Brodeur usually faces tougher opponents. This is a fair criticism, and
I examined this in a previous post for the years 1998-99 to 2008-09. I concluded that Brodeur faced slightly tougher teams than his backups, facing teams that took about 0.5 more shots per game on average. If we add this to the estimates above, it looks like Brodeur prevented about 1.1 shot per game on average.
If this estimate seems low (
it does to Brodeur), it may be because you are implicitly comparing Brodeur against a hypothetical goalie who never handle the puck rather than against an NHL goalie. Also, remember that not every instance of a goalie playing the puck prevents a shot.
I think you should add another disclaimer though:
3. Save percentage assumes that the criteria of a "shot" is standardized throughout the league, and there is evidence that this is not the case:
http://www.puckprospectus.com/article.php?articleid=351
Stats aside, anyone who has watched the Devils on a regular basis can remember more than one first period where either team officially had 0, 1, or 2 shots, and Doc Emrick was laughing, "Well it certainly seems like they had more than that."
I also posted
something about this in an earlier thread here. It does appear that New Jersey's home scorers record fewer shots. However, I'm not convinced of this effect yet, it could be that New Jersey purposely plays a different style of game as well. The other teams that have the largest observed decline in shots recorded at home over the past decade are Dallas, Minnesota, and Vancouver - all fairly defensive teams as well. If nothing else, the fact that these teams play with the lead more often at home may suppress total shots.
I know that it's been proven that for NHL goaltenders in general, save % does not go up as shots do. But it certainly seems that with Brodeur at least, his save % goes up when he faces more shots. Not just on a season by season basis, but also on a game by game basis.
I wonder if there is a correlation, where if a goalie faces an absurdly low number of shots (like dead puck era Brodeur or Ken Dryden), his save % tends to be lower. Or maybe it's something unique about Brodeur and the Devil's style.
This is the case for NHL goalies in general. It's most likely because of the fact that a good save percentage can cause shots against. When a team takes the lead - often because their goalie has had a good save percentage - the opposing team tends to start taking more shots that are of lower average quality. This means that 30-shot games tend to have higher average save percentages than 20-shot games.
At the same time, this effect does not appear to generalize to the season level. It appears to even out, as every goalie spends time playing while ahead or behind. If anything, it means that Brodeur's shot quality against may be lower on average, because he spends more time playing in the lead than most goalies.