Jerry Coyne has posted (with permission) an email exchange with Dan Barker. JC asked DB – evangelical turned atheist and co-president of the FFRF – “what he thought about the accommodationist claim that promoting compatibility between religion and science could turn the faithful towards science.” Barker’s answer is interesting.
I think you are right. I don’t know of anyone whose views on creationism changed as a result of hearing other religionists champion evolution. (Though I don’t doubt that could have happened. Well, I think it must have happened, given that some people do go through transitional processes, within religion and out of religion.)
I think the reason you are (mainly) right is that few believers hold much respect for the authority or opinion of other believers who disagree with them theologically.
There’s more, and then he ends with an equation:
Religion + Good Works = Good Works
Solve for Religion.