Based on the criteria of the link you provided, the largest metric affecting that was goals against--45% of the metric used...which includes the goalies proper.
We're arguing different things here. In both 2013 and 2015 Crawford co-won a Jennings--meaning the 'hawks were at least *tied* with the top team in the league for GA which is the largest metric of the formula in the link provided. In 2013 Crawford posted a 1.94 GAA seeing 26.53 SA/GP. In 2015 he posted a 2.27 GAA seeing 29.14 SA/GP.
In any universe 26.53 SA/GP is better than 2.91 SA/GP as a team metric. Those extra shots were being generated by something that the skaters in front of him were not doing as well as they did in years prior. Ergo, Crawford's job was harder in 2015 and he was more instrumental in the cup win *and* his Jenning than he was in 2013. The D might have been great in 2015, but it was worse than the preceding seasons.
And GAA is a terrible stat. As it's more of a team stat, and not specifically a goalie stat. And not arguing different things. The only point being made was to disprove your assertion that Crawford had to work a lot harder in 2015. That his play was more instrumental than anything in his Jennings. When in all reality, in 2015, Crawford was still playing behind the 2nd best defensive team in the NHL...
BTW, you're arguing that a 2.5 shots against increase paired with a 1/3 percentage point increase from 1.94 to 2.27 in his GAA means that he was better, and more instrumental in the Jennings in 2015? Doesn't make sense. An extra 2 shots per game is not a very large decrease in team defense. Especially when you look at the big picture with the corsi stats, and the fact that Crawford
still saw less shots than any other goalie in the NHL except one.
The fact remains, Crow still played behind the 2nd best statistically defensive team in the NHL in 2015, and saw less shots than all but one team, ergo his team defense in front of him was extremely instrumental in his Jennings. The team is always instrumental in the Jennings.
None of this is to take away from Crow. I've loved Crow for a long time, and was a huge fan of his prior to many, when people used to complain about soft goals and a lack of fortitude when it came to moving on after bad goals and such. He's a great goalie. And I've always argued for him. I'm still of the belief that he was a top 5 NHL goalie during his run. But Crawford did not work much harder in 2015 in comparison to his other years. Two extra shots a game is not working a lot harder...