LooseCannon said:
No, I agree with the statement that Hasek is better than Brodeur. Brodeur wasn't on a good defensive team; he was on the best defensive team. He's still an excellent goalie.
However, while a team wins a Stanley Cup, you simply do not win the Stanley Cup with a goalie who plays poorly. You can win with an average goalie on a hot streak or a spectacular goalie playing mediocre, but you don't win with a goalie who plays bad hockey. That's not true for any other position.
The goaltender position is, bar none, the biggest make or break position in hockey. That's why goalies have boatloads of Conn Smythes in relevance to their per capita makeup of championship teams.
I wouldn't call Brodeur an excellent goalie. He's had two excellent stretches in his career, but overall I'd settle on "very good".
As for your second point, lets look at the last ten years. Because I don't know whether you're right. I'd agree that goalie is the most important position in hockey; however, I'd say that this sentiment is believed in with too much conviction, and that is why goalies have more Conne Smythes. But I digress.
Year Average Sv% Winning save % +/-
2010 0.908 0.910 - Niemi +0.002
2009 0.915 0.908 - Fleury -0.007
2008 0.914 0.930 - Osgood +0.016
2007 0.919 0.922 - Giguere +0.003
2006 0.906 0.920 - Ward +0.014
2004 0.922 0.933 - Khabibulin +0.011
2003 0.919 0.934 - Brodeur +0.015
2002 0.918 0.920 - Hasek +0.002
2001 0.912 0.934 - Roy +0.022
2000 0.918 0.927 - Brodeur +0.009
Well, it certainly looks like better than average goaltending helps. Only one goaltender is less than their playoff average; Fleury. Just by looking at the numbers, there were 3 of what I'd call "very good" performances (0.014-0.018+; Osgood, Ward, Brodeur) and one "excellent" one (0.018-0.022; Roy). There is another good one, and then three more or less inconsequential ones, and a bad one. I think this shows that good goaltending definitely helps; but far from a dominant one is necessary if you have proper goal support.
EDIT: Actually, I should have noted that the listed goalies were rarely the ones with the best save percentage overall; typically those goalies were knocked out in earlier rounds. Goal support is more important on the whole I'd say.