Now I'm no advanced stats magician when it comes to hockey anyway, but immediately with this chart I sort of question Stone's placement. Pre-Michalek injury he was playing with Klesla or Schlemko. Then he played with OEL. Wouldn't that account for him being smack dab in the middle as "two way" right there? Especially considering his other D partners are in the "sheltered" category. Surely the games where he plays with OEL his placement would be different then the games earlier in the season.
Also I still have a huge problem with the idea of taking a human being's (the coach) decision and adding that into a stat somehow. It might not be totally useless but It basically guarantees I'll never trust any of these numbers at a glance unlike most baseball stats.
The fancy stats in hockey have a long way to go before they're close to as helpful as the baseball ones, and given the nature of the games I'm skeptical of whether they'll ever pull even, but I think the quality of competition and offensive zone start percentage numbers are useful for context. I would never say a player is better or worse than another player just based on those metrics, but if two players have similar stats otherwise, I'd rather have the one who performed against tougher opponents or in less favorable circumstances.
In this case, OEL and Stone have similar Corsi Relative numbers, but OEL put up those numbers against tougher opponents. He also started 55.6% of his shifts in the defensive zone, as compared to only 45.2% for Stone, so the ice was even more tilted against him.
The point is: no one stat is a magic bullet, but the more information you have to work with, the better an understanding of a player's value you can ascertain.