Growing up, certain facts about hockey were drilled into my head as common knowledge. Bobby Orr was the greatest hockey player ever. Ulf Samuelsson is the physical incarnation of evil. The goaltender is a team's most important player in the playoffs.
I realize now that the first two "common knowledge" facts are only common knowledge in the city of Boston. For years, though, I still believed goaltending was the deciding factor in the Stanley Cup Playoffs. I'm starting to suspect that the last fact has more to do with Ken Dryden than statistics.
My parents saw Dryden steal a 1971 series for the Canadiens against a Bruins team that was arguably better than the ones that won the cup in 1970 and 1972. This left an impression in their minds: a hot goaltender can ruin everything. It's true that in the most surprising recent upsets (Montreal beating Washington and Pittsburgh in 2010, Tampa beating Washington and Pittsburgh in 2011), unexpectedly good goaltending was the difference. But overall, goaltending appears to be more of a wildcard factor- capable of stealing series, but not a Stanley Cup.
Since the lockout, there is no discernible pattern in the goaltender quality of Stanley Cup winners. Their regular season SV% ranges from 1st (the 2011 Bruins) to 23rd (2010 Blackhawks). Only Boston and Anaheim had goaltenders in the top 10 in SV%.
Other factors are also all over the board. Goals against displays a weak connection to winning, at best. Special teams have no bearing, which makes sense given that fewer penalties are typically called in the playoffs. Powerplay quality is especially irrelevant.
It appears that the one weakness a team cannot afford to have in the playoffs is lack of scoring. Every winner since the lockout has been top 10 in regular season scoring. In fact, out of the 12 teams to make it to the Stanley Cup Finals since the lockout, 11 were among the top 10 in scoring. Only the 2006 Edmonton Oilers, at 15th, were below this marker.
The Oilers are an interesting case. One could argue that, had Roloson not gotten hurt in the Finals that year, they would be the exception to this rule. However, he did, and they lost, so the rule stands: your team must be top 10 in scoring to win a Stanley Cup, no matter how well your goaltender plays.
Even last year's Bruins prove this rule. Tim Thomas played phenomenally in the Finals, but he couldn't have won that series alone. He had a 1.67 GAA in his three losses- hardly something to complain about. It wasn't until the team started scoring that the Bruins won games.
This all means that Philadelphia and Pittsburgh, with their incredible offense and incredibly mediocre goaltending, have a better chance at the Cup than the New York Rangers or St. Louis, who are both out of the top 10 in scoring. In all likelihoods, neither the Rangers nor St. Louis will even make the Finals.
Dryden won the Cup for Montreal in 1971. It's possible that Lundqvist or Elliot are good enough to break this rule. But things have changed since the 70's. If I were a betting gal, I would keep my money on Boston, Detroit, or Pennsylvania.