... Well, any Corsi-based rating - in other words, a rating that goes off of shots for and against while a player is on the ice - isn't going to be friendly to Jack. Even this season, which is supposedly his best ever, Johnson is last among Kings' defensemen in relative Corsi ratings. Johnson does a little better in Fenwick ratings, which are simply Corsi ratings without blocked shots.
The obvious counter-argument to this is that if you ask fifteen different hockey fans what determines a quality shot, you might get fifteen different responses. It's not an exact science, and I'm the first one to say so. It's merely to help illustrate the details which slip past our minds while we're observing the games, and tries to build some form of structure to track performance. Watching the games without understanding statistics is just as much of a flawed perspective in my mind as knowing the stats without watching the games.
My opinion of the new contract is a positive one, not only because I personally believe that Johnson will get better defensively as he develops as a player, but because I've grown attached to him emotionally (as I do to every Kings' player who is part of the team for several years or more), so my feelings DO carry a clear bias. If I were looking at Jack from a purely statistical and cold point of view, I would have more of a negative reaction to the signing. He still has work to do defensively; I just happen to think he will put in that work and learn to excel in that facet of his game.