[donw]

The point is not that creationism is an obvious case of twisting the facts to fit theories.

It is that, if you want to have any hope of bringing a creationist over to your side, you need to be able to understand and articulate both their arguments, and their point of view.

If you can establish that you understand them, they are going to be a lot more receptive to you asking the hard questions about their beliefs (this is best done by asking them to convince you to be a creationist, and then asking those hard questions).

Calling those people idiots does nothing other than give them a legitimate reason to dislike both you, and by extension, other people that "believe in evolution".

Somewhat related to that, creationists tend to be deeply religious, so books like The God Delusion -- which I very much enjoyed, by the way -- are almost guaranteed to turn off a creationist. It would be better to recommend books that explain evolution through a Christian world-view, as they will have a much easier time relating to the material.