Which is more valuable for real discussion: hearing an opinion you disagree with argued well and thus coming to see why it is widely held, or hearing a view you

Which is more valuable for real discussion: hearing an opinion you disagree with argued well and thus coming to see why it is widely held, or hearing a view you disagree with argued poorly, further convincing you that its adherents are simply morons? If you're not getting the opinions you want to read, it's easy enough to pick up a different paper. The danger of a bad op-ed is tricking people into thinking they are getting both sides of the story when they aren't.