I think this distinction is not made clear enough in English class. To me, when we were writing essays, there seemed an inordinate emphasis towards the way we wrote it rather than the ideas that we were trying to express. This kind of skewed emphasis is what allows someone to “BS” a paper – cloak rather unthought-out or worthless ideas using fancy language and get a good grade, and is what allowed a physicist to submit a BS paper to a literary journal and get accepted (http://en.wikipedia.org/wiki/Sokal_affair – although this was very well planned). When the impression is that students are judged by the quality of writing rather than the quality of ideas, then we are attuning students to judge based on outside appearances; we are teaching propagandists.
Both need to be stressed. Beautiful writing without good ideas is “propaganda.” Beautiful ideas without good writing are ideas that will never reach the public. We need both.