Quote Originally Posted by Sephrick View Post
Well, they have mentioned that playing the role of a job may cause some abilities to become unusable until you switch back to being the originating class. So, it's completely possible that the storyline for CON > WHM will be "you have MP, stand in back and cast cure."
Actually it was losing ability to cross-class skills from other classes. Native class skills should still be intact, unless that ends up being some ninja edit.