The polygon write up is funny. Iirc in the Alpha the Yokai type enemies or bosses, are not governed by the same stamina rules as the humanoid characters. Each time you hit a Yokai you take away some of their "stamina" once you deplete it completely you can stunlock them for a few seconds and deal massive damage. Pretty sure Yokai bosses are governed by the same rules, because I remember using it to my advantage during the boss fight in the boat in the alpha.
The thing is, though, if you turtle too much you'll never be able to deplete their stamina because they can regain it back quickly. The mechanic forces the player to be aggressive and discourages being too passive in the fights. If polygon is being too careful during boss fights I could see the fights taking a while lol.
Thats going from the Alpha, though I don't think much changed. The game was probably designed around this mechanic so I doubt they tampered with it too much, if at all.