So many of the mobs killed throughout the game can be skinned. Mining is "here and there" to which most times you have to go a tad out of your way when you spot a mine. As is the same with herbalism. With skinning, you're right there to gather the mats.
Doujhe can go and get just about any minerals needed for whatever. He's got his mount and can get there and make rounds quick. The same goes for Daajhn and herbalism. If I need any of these, I can go farm them with intent. Skinning is more of a "while I'm there" type gathering profession.
So if the other professions are aptly being taken care of, why not just gather something quick "while I'm there"? Dhistens will keep tailoring, as that will come in handy, but Dehrange will stay to fill the leatherworking craft which Dhistens will be dropping in order to pick up skinning.