I have to second annalex's comment, RM. Orthodoxy uses heretic and heresy in almost the exact way he has described Roman Catholic usage, the only difference being that for us a heretic is a heretic is a heretic whether or not they realize they are a heretic. To state that someone is a heretic or some belief heresy is merely a statement of theological fact within the contemplation of The Church. Neither are terms in any way synonomous with or equivalent to liar or idiot.
It is helpful to think of it his way...all liberals are heretics but not all heretics are ugly
Is that helpful?