You can break down a skaters game by his passing, shooting, skating, and reads. Those are the four critical areas you look at. What a player does without the puck can be taught.
With Muzzin, sometimes he can connect with long, stretch passes, and other times he passes to an already covered passing lane or gives the puck right up or ices it when there is no pressure on him. When there is pressure on him, he panics.
His shooting is unpredictable. Sometimes he can get it through, then he'll go through a long stretch where all he can hit is a blocker's shinpads and the puck rockets back out and he's caught chasing a player.
I wouldn't consider Muzzin a phenomenal skater but he's adequate when he's skating with the puck, so long as he's not being pressured like when the Wings chased him behind his own net and he flubbed the puck right to them which led to a goal.
The most questionable and inconsistent part of his game are his reads. Bad pinches in particular, but another thing he does that drives me crazy is how he will come down the left side boards and try to put the puck on net from a bad angle, and what tends to happen on those plays is a misfire where the puck wraps back along the boards and springs the opposing team on a counterattack.
There are so many holes in his game that I'm sure you and many others are well aware of. The positive things that he provides on the ice isn't enough to hide his flaws and I question if he even has the wherewithal to make the necessary improvements to be considered a legit top 3-4 defender on this team. I've seen him get knocked off the puck easily on numerous occasions. I've seen him leaving his zone when he should be the last man back. I see a player who leaves my head scratching much like others saw the same in Jack Johnson, a defender who has a better set of skills who also struggled with the mental part of the game.
Now I urge those who see the positives more than the negatives in Muzzin to please enlighten us as to what makes him so special that he should be handled with care. I view Muzzin as an asset that should be dealt before he regresses any further. To me, he's the second coming of Joe Corvo.