I must admit that the only context I've heard DD in before was by the hosts of connotations, who won't allow DD fic in the con zine. Quite exactly what DD *is* in their view, I am not sure, but I know the main reason for their prejudice is the number of trite and mediocre fics that are written within this theme. I am quite sure (well, hopeful!) that they wouldn't have a thing to say against your stories, and that it's not a prejudice against discipline per se. Yes, I think it's a confusing term and best avoided; people ought to know what they're getting into when a fic is labelled bdsm, and the extra warnings do not go amiss for those who don't!