I would have to agree with the one episode (or however many it is) recast of Carolyn. Don't know what that stand-in for Nancy's name was, but GOD she was awful! Nancy is Carolyn, Carolyn is Nancy. That would be like getting Farrah Fawcett or some absurdity to stand in for Lara Parker as Angelique for one episode. Sorry, you may as well just cut her parts from the script...
You know, now that I think about it, that's not a bad idea. Wouldn't it have been uproarously funny if Roger Davis had've played both Carolyn AND Jeff (isn't that who was in the scene with her during that ep? maybe it was Tony Peterson) whoever it was, it still would've been funny.