You raise a good point, Katherine. My contention would be that since no idea that is debatable (as ideas that are debated tend to be) is self-evident, presentation and credibility are a huge part of how valid we see an idea in relation to the topic to which it is being applied. The credibility of an argument is seriously damaged when the other side and observers see that the advocate for said argument is unwilling to claim responsibility for that argument. I think that's more or less what Lauren was saying in her excellent piece.