My friend and I are still working our way through the story, in order. Currently in Path of Fire right now. So when we get Dailies for End of Dragons, or the new Secrets of the Obscure areas, that means we wont complete dailies simply because we don't want to spoil story just to get some rando mini dungeon in a zone we've never gone to.
Maybe if you haven't started the content, dont present the selection of daily challenges?