The conventional wisdom on goalies is that you shouldn't pay them because performance is so up and down. If you plot goalie pay and goalie performance it's a total mess, there's not much of a pattern to it.
And then there's Bob, who has led the league in goals saved above replacement two years in a row, by a large margin. Taking shot quality into account, he should have picked up his 3rd Vezina last year. And he accounts for about as many wins as the very best forward in the league, in terms of value over replacement.
There's no question that his performance of late is worth well over $10m per season. The question is whether you expect him to continue that, and continue to defy the pattern that seemingly every other goalie is a part of. If he does, he's basically the Dominik Hasek of his generation. I don't think anyone should look back at Hasek from his age 29-37 year old seasons and say he shouldn't have been paid like one of the very best players in the league. Hasek was worth, in today's money, well over $10m per. I don't know if Bob can be like Hasek, but I also don't know that he can't be. It's a very tough decision.