Summer Rose
Red Like Roses
I see why Murray started to be really simple: he's Sullivan's guy and Sullivan thinks he's better. No matter how well Fleury played, he was never the #1 goalie this season. It has always been Murray's team, and Sullivan was just riding Fleury's hot streak. When it appeared it might be over, Sullivan went back to his actual starter.
This is exactly how I see it. It would have been a mistake to put Murray back in in the middle of Fleury's hot streak, but at the first sign it was over, you put your regular guy back in (now that Murray is available again). It happens all the time.