Edge
Kris King's Ghost
I disagree, from a technical standpoint his skating is excellent, the way he moves for a big man is almost unheard of.
Quinn Hughes is also an elite skater who is about 50 lbs lighter then Day, so yes he will change direction quicker based on the laws of physics.
To say that Sean Day is "good skater for his size" is to undermine him. Sean Day would skate circles around peak Aaron Ward.
The thing with Day is that his skating is so fluid, it's silky. He can cover a lot of ground, change direction and get to places with very little wasted effort or motion. Unfortunately, because he makes it effortless, it almost looks like he isn't trying or that he isn't skating. It's simply that he doesn't make skating look like an endeavor.
A lot of times I find that people associate skating with straight-ahead speed, aka how quickly someone can zoom from Point A to Point B. But skating is also about mobility, agility, being able pivot, turn, shave off a split second by handling a better angle.
When we look at the work that Barb Underhill does, a lot of it is about efficiency and using momentum. It's not so much that players enhance their physical abilities under her training, so much as they learn to use their abilities more effectively.
Sean Day is a tremendously effective skater, more than he is a Pavel Bure speedster. That's why it's so easy to say, "if he can even be about average in everything else, his skating is enough to have him make it."