Mark Stuart is not a very good NHL defenceman, but he is good enough that he would be played by most teams. This take into account that most teams like to have at least one defenceman who is tough and gritty. Stuart is not a bad option as a 5/6 (bottom pair) defenceman. The problem is he is slotted in as a 3/4 defenceman at worst. This has not always been the case, but since it started last season Mark Stuart has become the epitome of a player that is not hated for how bad he is, but because he plays too many minutes for a player of his calibre.
This is not to say that Stuart had a good season for a 5/6 defenceman. He often made poor reads and went for the hit instead of making the safe choice of defending the play. While aggressive pinching can lead to more shots for, bad decisions on when to pinch can lead to defensive break downs and odd-man rushes the other way. The fact that Stuart takes these risks while being a noted defensive defenceman and not a very good one at that should lead Jets fans to worry about his contract. He has three more years with the Winnipeg Jets under his current contract and the team absolutely loves him.
This graph shows that Stuart is a middle of the pack third pairing defenceman except when it comes to CorsiFor. It is reasonable to assume that playing with Jacob Trouba has impacted his shot generation and that the boost in numbers is not related to his play at all, but instead the play of his partner.
While the chart does not show it, Trouba has credited Stuart with helping him transitioning to being a good professional hockey player. This work should not be discounted, but one would hope that there are other players on the team who can do the same mentoring job.
Currently the Jets management group and coaching staff loves Mark Stuart and with his contract that probably means that he is going nowhere anytime soon. While the Jets are incredibly thin on left defence, Stuart contributes to the issue instead of help fix it because he is not very good and he is aging. This is not the same issue as Ben Chiarot being a bit of an unknown commodity because he has yet to play a part from Dustin Byfuglien. This is a player who makes poor reads and struggles at the best of times. While Stuart is a NHL defender, he is not the type of defender one wants in a top four and he certainly is not one worth over $2.5 million/season.