I think you missed the point on the duplicate content myth. It doesn’t hurt rankings at all for your website, only for the page(s) that has the duplicate content. I prefer to get my facts straight from the Google engineers and that’s what they are saying, and it’s backed up by plenty of examples online. At worst duplicate content is a zero sum game, and that’s the only point that’s really being made here. It doesn’t help and it doesn’t hurt.