I rarely use stoneskin, though I do main as a Scholar. But when I did play as a White Mage I feel I was a bit too trigger happy with it and always tried to keep it up on every player; I was new, lol. But I will say I have noticed this as an increasing trend. I guess it's the WHM equivelant to Galvenize, and preventing overhealing, you just notice it more because it isn't connected to a heal like Adlo or Succor.