To try to look at the issue of coaching impacts on goaltending, I pulled the team save percentage numbers for every coach from every season since 1948-49 (using unofficial numbers to fill in the gaps for 1948-49 to 1954-55). We can adjust all those for league average, to get an expected save percentage for each coach, all the way from Tommy Ivan in first place (0.78) to Steve Kasper at the bottom (1.23). Those numbers are my adjustment factor, which means that in a .900 average environment, Ivan's goalies would put up a .922 while Kasper's would come in around .877.
For partial seasons (where a coach was hired or fired mid-year), I'm just pro-rating results. That's not entirely correct, as a lot of times things turn around under a new coach, but it's way easier from a calculation perspective and will likely wash out mostly for any longer-tenured guys.
I also looked at the average team discipline (i.e. power play opportunities relative to average) for each coach, because that's something that impacts goalies. We also don't want to double-count, i.e. if a team is disciplined but a coach's teams are always disciplined, then it's kind of already "baked in" to their coaching rating.
Lastly, I ran the numbers for backup goalies and calculated their numbers playing with the given goalie, as well as their career numbers while playing for all other teams, which will also give us a backup rating to help add information to the coaching analysis.
Hopefully that all makes sense. If anyone notes any errors I'm happy to make corrections, this was a bit rushed together and may need to be refined based on feedback.
Ken Dryden is the easiest, since he played all of his meaningful regular season career for one coach:
Goalie | From | To | GP | SA | Sv% | LgAvg | SoS | Bkp SoS | Bkp SA | Bkp Sv% | Bkp Other | Bkp GP | Coach | GP | % w/G | Coach | Backup | Coach Disc | Team Disc |
Dryden | 1972 | 1979 | 391 | 10872 | 0.921 | 0.893 | -0.09 | -0.34 | 4576 | 0.897 | 0.885 | 314 | Bowman | 2141 | 18% | 0.91 | 0.89 | 0.93 | 0.89 |
Explanation of terms:
SoS is strength of schedule pulled from the outstanding Hockeygoalies.org
Bkp Sv% - save percentage while teammates
Bkp Other - career save percentage adjusted to league average when not playing with that goalie
(If goalies did not have any games on other teams, I just assumed league average)
Bkp GP - weighted average career GP of the backup goalies
% w/G is the percentage of the coach's career that he shared with that goalie
Coach Disc and Team Disc are team discipline ratings using power play opportunities against relative to average
All the averages were weighted using shots faced
For all the ratings, below 1 means easier for the goalie, and above 1 means tougher for the goalie
Notes for Dryden:
- he played a far more difficult strength of schedule compared to backups than any of the other post-expansion goalies
- his backups did far better when playing with Dryden than they did elsewhere
- Bowman is one of the better defensive coaches (unsurprisingly) with a 0.91 rating
- Dryden's backups did even better than they would expect given that they were playing for Bowman (although that should perhaps be expected since they played easier opposition)
- Dryden's teams were more disciplined than Bowman's average (even though Bowman's teams were typically very disciplined)
- In summary, Ken Dryden got an obviously huge team lift from his coach and team defence
Moving on to
Patrick Roy:
Goalie | From | To | GP | SA | Sv% | LgAvg | SoS | Bkp SoS | Bkp SA | Bkp Sv% | Bkp Other | Bkp GP | Coach | GP | % w/G | Coach | Backup | Coach Disc | Team Disc |
Roy | 1986 | 1988 | 138 | 3640 | 0.889 | 0.878 | -0.02 | 0.00 | 2722 | 0.887 | 0.866 | 355 | Perron | 287 | 48% | 0.95 | 0.85 | 0.89 | 0.87 |
Roy | 1989 | 1992 | 217 | 5916 | 0.910 | 0.884 | -0.13 | -0.09 | 3032 | 0.882 | 0.871 | 241 | Burns P | 1019 | 21% | 0.90 | 0.92 | 0.83 | 0.79 |
Roy | 1993 | 1995 | 173 | 5127 | 0.906 | 0.893 | 0.00 | -0.20 | 1445 | 0.874 | 0.889 | 174 | Demers | 1007 | 17% | 0.99 | 1.13 | 1.00 | 0.95 |
Roy | 1996 | 1996 | 39 | 1130 | 0.907 | 0.898 | -0.01 | -0.07 | 1983 | 0.909 | 0.891 | 416 | Tremblay | 159 | 25% | 0.96 | 0.83 | 0.97 | 0.90 |
Roy | 1996 | 1998 | 166 | 4816 | 0.917 | 0.904 | -0.12 | -0.10 | 2432 | 0.905 | 0.891 | 379 | Crawford | 1169 | 14% | 1.02 | 0.88 | 1.03 | 1.05 |
Roy | 1999 | 2002 | 249 | 6455 | 0.917 | 0.906 | 0.00 | -0.06 | 2314 | 0.912 | 0.901 | 282 | Hartley | 944 | 26% | 1.02 | 0.89 | 0.97 | 0.98 |
Roy | 2003 | 2003 | 63 | 1723 | 0.920 | 0.909 | 0.04 | -0.03 | 593 | 0.916 | 0.912 | 214 | Granato T | 215 | 29% | 0.99 | 0.95 | 0.98 | 0.99 |
Total | 1986 | 2003 | 1045 | 28807 | 0.910 | 0.895 | -0.05 | -0.09 | 14521 | 0.895 | 0.887 | 281 | All | 851 | | 0.98 | 0.93 | 0.95 | 0.93 |
Notes:
- Patrick Roy likely got a lot of help from his team in the early years as a Hab (1986-1992)
- It's tough to fully rely on the number for Jean Perron here since 48% of his games were with Roy in net, however the backups did outstanding under him relative to what they did on other teams, and those Habs were very disciplined
- I already discussed Pat Burns and Roy in this thread - Burns is one of the best defensive coaches ever, and the backup results fall right in line. Montreal was also an extremely disciplined team during those years.
- Playing for Jacques Demers, on the other hand, was tougher. Coaching numbers say average, backup numbers say even tougher than that. It's not surprising that Roy's relative numbers dropped by a lot over those seasons. Point on the backup numbers though - I'm assuming Andre Racicot is league average since he doesn't have a non-Roy sample, and there's no way Red Light Racicot was actually that good. So the real backup numbers would likely be closer to average.
- Patrick Roy's Colorado years are particularly interesting, because coaching and backup numbers tend to move in tandem for almost every situation, but for Roy in Colorado they diverge wildly
- The numbers for Crawford and Hartley suggest that Roy faced slightly tougher than average shot quality, but his backups did far better playing with Roy in Colorado than they did over the rest of their careers
- You can make your own conclusions on that one, personally I think the backup numbers are likely more accurate (and there were not any major strength of schedule impacts for Roy's playing partners in Colorado)
- Overall: Roy's teams were very disciplined, his backups did great playing playing with him, but his coaching numbers are closer to average (again mostly from the Demers years which seem legit and the Crawford/Hartley results which are more mixed)
Next is
Dominik Hasek:
Goalie | From | To | GP | SA | Sv% | LgAvg | SoS | Bkp SoS | Bkp SA | Bkp Sv% | Bkp Other | Bkp GP | Coach | GP | % w/G | Coach | Backup | Coach Disc | Team Disc |
Hasek | 1991 | 1992 | 25 | 506 | 0.897 | 0.888 | 0.02 | -0.09 | 3728 | 0.896 | 0.889 | 835 | Keenan | 1386 | 2% | 0.97 | 0.93 | 1.11 | 1.19 |
Hasek | 1993 | 1995 | 127 | 3493 | 0.923 | 0.895 | -0.15 | 0.00 | 3095 | 0.885 | 0.890 | 638 | Muckler | 648 | 20% | 0.96 | 1.04 | 1.00 | 0.99 |
Hasek | 1996 | 1997 | 126 | 4188 | 0.925 | 0.902 | -0.07 | 0.06 | 1438 | 0.901 | 0.896 | 137 | Nolan | 471 | 27% | 0.92 | 0.95 | 1.07 | 1.10 |
Hasek | 1998 | 2001 | 238 | 6689 | 0.928 | 0.906 | -0.06 | -0.06 | 2719 | 0.906 | 0.906 | 489 | Ruff | 1774 | 13% | 0.99 | 0.99 | 0.98 | 1.04 |
Hasek | 2002 | 2002 | 65 | 1654 | 0.915 | 0.908 | 0.07 | -0.16 | 503 | 0.911 | 0.912 | 365 | Bowman | 2141 | 3% | 0.91 | 1.01 | 0.93 | 1.01 |
Hasek | 2004 | 2004 | 14 | 324 | 0.907 | 0.911 | -0.15 | -0.10 | 1821 | 0.916 | 0.912 | 590 | Lewis | 251 | 6% | 0.99 | 0.95 | 1.02 | 0.91 |
Hasek | 2006 | 2006 | 43 | 1202 | 0.925 | 0.901 | -0.06 | -0.11 | 1141 | 0.900 | 0.895 | 265 | Murray Bry | 1239 | 3% | 0.96 | 0.95 | 0.97 | 0.99 |
Hasek | 2007 | 2008 | 97 | 2164 | 0.909 | 0.907 | 0.00 | 0.04 | 1777 | 0.908 | 0.906 | 660 | Babcock | 1301 | 7% | 0.98 | 0.97 | 0.99 | 1.02 |
Total | 1991 | 2008 | 735 | 20220 | 0.922 | 0.903 | -0.06 | -0.03 | 16222 | 0.902 | 0.901 | 447 | | 1223 | | 0.96 | 0.99 | 1.00 | 1.04 |
Notes:
- Under Keenan and Muckler, Hasek was probably facing slightly easier than average shots. The backup numbers aren't great under Muckler, but that might have just been Fuhr being a bit washed up at that point.
- The Ted Nolan years are interesting. Nolan has a very good score, but it is probably a bit inflated by peak Hasek being 27% of it. The backups did pretty well too though.
- Lindy Ruff: 0.99 coach rating with team less disciplined than usual, 0.99 backup rating. About as average as you can get. I have always maintained that there is no evidence to suggest that Hasek was getting any kind of significant team lift during this period, and these numbers strongly back that up.
- Bowman has a great defensive reputation, but I'm not sure how much that was still relevant by 2002. The backups are average, and his teams were much less disciplined than normal.
- For the rest of Hasek's career, he had easier than average under Bryan Murray and a bit easier but close to average under Babcock
- Overall, Hasek's coaching numbers are actually slightly better than Roy's, but the Sabres were less disciplined than those coaches' teams were normally. Also, Hasek's backup results are almost right on league average. Overall, his environment was probably slightly better than league average.
Finally, here's
Martin Brodeur:
Goalie | From | To | GP | SA | Sv% | LgAvg | SoS | Bkp SoS | Bkp SA | Bkp Sv% | Bkp Other | Bkp GP | Coach | GP | % w/G | Coach | Backup | Coach Disc | Team Disc |
Brodeur | 1994 | 1998 | 301 | 7302 | 0.916 | 0.901 | -0.06 | -0.07 | 2607 | 0.903 | 0.899 | 377 | Lemaire | 1262 | 24% | 0.91 | 0.96 | 0.86 | 0.78 |
Brodeur | 1999 | 2000 | 142 | 3525 | 0.908 | 0.906 | -0.13 | 0.05 | 593 | 0.887 | 0.906 | 406 | Ftorek | 443 | 32% | 1.06 | 1.20 | 0.98 | 0.93 |
Brodeur | 2001 | 2002 | 145 | 3417 | 0.906 | 0.905 | -0.12 | -0.27 | 664 | 0.893 | 0.908 | 485 | Robinson | 501 | 29% | 0.98 | 1.17 | 0.92 | 0.82 |
Brodeur | 2003 | 2004 | 148 | 3551 | 0.915 | 0.910 | -0.08 | -0.51 | 375 | 0.944 | 0.896 | 157 | Burns P | 1019 | 15% | 0.90 | 0.54 | 0.83 | 0.75 |
Brodeur | 2006 | 2006 | 73 | 2105 | 0.911 | 0.901 | -0.14 | -0.2 | 295 | 0.881 | 0.889 | 191 | Lamoriello | 53 | 89% | 0.93 | 1.07 | 0.72 | 0.73 |
Brodeur | 2007 | 2007 | 78 | 2182 | 0.922 | 0.905 | -0.19 | -0.18 | 144 | 0.889 | 0.894 | 191 | Julien | 1274 | 6% | 0.92 | 1.05 | 0.94 | 0.68 |
Brodeur | 2008 | 2009 | 108 | 2959 | 0.919 | 0.909 | -0.12 | -0.03 | 1697 | 0.916 | 0.900 | 243 | Sutter Bre | 410 | 26% | 0.95 | 0.84 | 0.96 | 0.91 |
Brodeur | 2010 | 2011 | 133 | 3317 | 0.911 | 0.912 | -0.04 | -0.18 | 1040 | 0.913 | 0.905 | 291 | Lemaire | 1262 | 11% | 0.91 | 0.91 | 0.86 | 0.80 |
Brodeur | 2012 | 2014 | 127 | 3097 | 0.904 | 0.914 | -0.02 | -0.01 | 2276 | 0.913 | 0.911 | 389 | DeBoer | 1179 | 11% | 0.98 | 0.98 | 0.94 | 0.99 |
Total | 1994 | 2014 | 1255 | 31455 | 0.912 | 0.906 | -0.09 | -0.15 | 9691 | 0.906 | 0.901 | 321 | | 892 | | 0.94 | 0.96 | 0.89 | 0.82 |
Notes:
- Pretty strong team environment under Jacques Lemaire, to nobody's surprise, although the backup results aren't quite as good as the coach numbers
- Robbie Ftorek wasn't a good defensive coach. This is easily the toughest environment Brodeur had to play in, and very likely the toughest save percentage environment any of these 4 goalies faced in their careers.
- Robinson is around average, but the Devils were much more disciplined under him than on his other teams
- Burns shows up again, with ridiculous backup numbers (in a very small sample size though) and incredible team discipline as usual
- Lamoriello is tough to evaluate since his entire short career is basically just with Brodeur in net. The backup results aren't great in a tiny sample size, but the Devils continue to be super disciplined.
- Claude Julien is another coach that had great defensive results during his career (almost as good as Burns or Lemaire). Again, the backups don't quite track, but it's only 144 shots (running theme for the high-workload Brodeur, we can only really analyze backup results in aggregate).
- the Brent Sutter years and Jacques Lemaire second time around also look pretty favourable
- Deboer looks like right around average
- Overall, coaching results suggest Brodeur had an easier time of it than Roy or Hasek, especially when you factor in his teams being quite a bit more disciplined than they usually were for those coaches. But the backup results lag a bit behind, so maybe there were other impacts.
My quick-and-dirty overall estimates for difficulty of environment in terms of its effects on save percentage:
1. Ken Dryden: 0.91
2. Patrick Roy: 0.95
2. Martin Brodeur: 0.95
4. Dominik Hasek: 0.98
Those are just my guesses. If you think playing in Colorado was actually tougher than average, then you should slide Roy down. I think overall Roy had the worst backups (with Racicot not being fully adjusted for) and Hasek had the best, while Hasek was the only one that had to deal with poor team discipline, and that is also informing my estimates to some degree.
The other major point from this analysis is that Roy's peak under Pat Burns was very likely not close to as good as it looks statistically. If you're someone who focuses heavily on big peak, you should check to make sure you aren't overrating Roy in Montreal.
For the O6 guys, I can't really do a full backup analysis so it's not quite apples to apples, and I don't have full team disicipline numbers going all the way back, but I'll post the simplified coaching numbers in another post and do a quick discussion on those too.