Teaching Ethics

My first set of Medieval Lit papers has come in today, and they look pretty decent thus far. But they gave rise to a few interesting ethical questions.
When teaching this particular medieval class, I use the SEAFARER program (no link, since it's password-protected due to copyright issues), an early hypertext program developed at Loyola by my dissertation director. Seafarer is organized around "modules" such as Rank, Labor, Monastic Life, Penance, The Book, etc. Each of these includes a narrative, lexicon, images, bibliography and "link" questions that students can answer for their papers.
Now here's the ethical issue: Seafarer's ideological approach is much more marxist than anything I'd regularly teach and is far away from anything that I actually believe in. That's exactly why I teach it, so that students get exposed to some of the variety of medieval studies instead of getting The World According to Drout.

But this post isn't just an exercise in self- back-patting. I'm having major second thoughts about the approach I've taken.
On the one hand, great to give students a taste of opinions and interpretations I don't have, avoid indoctrination, etc. On the other hand, I am pretty certain that marxism, and marxist interpretations of history, are wrong. Therefore it would seem that I'd have an obligation not to expose students to these incorrect interpretations.
Ah, but down that path lies indoctrination. Most of my colleagues at Wheaton are, it seems to me, dead, absolute certain that (just to give an example), the war in Iraq was wrong. And many of them teach this in their classes. I am simply not comfortable with that kind of use of the classroom. First of all, I want my students to think for themselves. Secondly, I think attempted indoctrination nearly always backfires.
But where do you draw the line? I do say things in class like "A recent critic claimed that Asser's Life of King Alfred is a forgery by Byrhtferth. That critic is wrong." Should I hem and haw about that? At a certain point, students get absolutely (and reasonably) sick about academic waffling. I have a friend in medieval studies who, in a seminar at the Newberry Library, used to say that every question was "fraught." 'The relationship of Beowulf to the Blickling homilies is 'fraught,'' 'The connection between the Dream of the Rood and the Ruthwell Cross is 'fraught'' etc. At a certain level it's an annoying graduate-student tic: saying things are 'fraught' and refusing to give an opinion on them suggests that you've read all the criticism and have an open mind.

But in the end it's your job to have an opinion about the big questions in your field. You have a responsiblity to give the "on the one hand/ on the other," but you have to figure out where you stand. And you need to express these ideas to students without getting them hopelessly confused by the critical opinions. Academics hate sound bites (sometimes fairly), but you can't communicate everything as a lengthy treatise.

Which brings me around to the original question, but from a different angle now. Somehow there's a distinction to be made between ideological approaches that I believe are wrong (but that could, potentially, produce valid insights simply by directing attention in different directions) and facts that I think are wrong, but that's not the easiest line to draw (whimp out, cliched, safe comment).

So I just make it up as I go along (the truth).