I have a big, big problem with that chart. Stralman didn't come onto the team until 2011. He never played with Tyutin as a Ranger. From 2009-2011, the team was nowhere near the quality that it was 2011-2014. The numbers are just not comparable. It's like taking the temperature in Bali and the temperature in Boston and using them to find an average global temperature. Using that chart to evaluate Staal also doesn't address who Staal's partners were during that time. Staal-Girardi was an excellent partnership, but one destined not to show great possession numbers because both players are off-puck players. It's why the pair got broken up as soon as possible. Beyond that pairing, I seem to remember Staal being with Rozy and MDZ most of the time. Hardly partners conducive to good possession numbers, either.
The chart was just to figuratively compare Stralmans dominance relative to previous Rangers dmen as well his ability to drastically improve their play vs. without their play. I know it'll be brushed aside as having no competition, but performing better than MDZ, Staal, Girardi, Tyutin, Roszival, etc who were all top 4 dmen for the majority of their Rangers tenure speaks volumes of his skill level.
The chart clearly points out that Stralman has been Staal's best defense partner and the Rangers decide to let go off that after 1 full season with the pair together. What's worse is that they sign an aging Dan Boyle who is utterly incapable of handling the same ES minutes with dominance as he used to be. This is quite inexcusable.