This is perhaps already obvious to many of you, but I had a bit of a 'release' revelation a few days ago; I'm much less daunted by theist discussion thanks to it. Sorry if this sounds pompous, but I'd like to share.
'Pigeon Chess' is the best analogy I've heard so far to describe an atheist/theist discussion, but I kept wondering about ~how~ a theist manages to deny/dismiss fact/evidence even when it's right in front of them.
If you think to our education, we spend the first part of our lives building our minds by mimicking a few trusted 'authority figures' who are supposed to show us what's good and dangerous in the world (and being doubtful/in fear of anyone/anything else), but eventually we gain enough experience to start making conclusions of our own from what we experience around us.
Religious people are just people who have never left the first stage. Just as children, they focus on their 'authority figures' for (emotional) reward and punishment; they just 'blank' any information from any other source as 'wrong' or 'bad'.
I can almost compare a 'follower' education to training a lab rat: the reward is food if he does the 'good thing', and punishment is an electric shock if he does the 'bad'. Eventually the rat will grow to fear certain things and appreciate others, even without an actual reward being given. When released into the world, he will regard with incomprehension (and perhaps fear) anything different from the environment he was trained in, and run to his 'education environment' for safety if he can. Trained rats together will behave the same way, but as a pack.
The key here is emotion: the 'reward' for a theist comes directly from a leader approving a followed behavioural pattern, whereas the 'reward' for a thinker comes (first) from ~himself~ when he achieves understanding and uses it to a successful result/conclusion.
So, for a theist, any information not from certain sources or outside their programmed behavioural pattern ~doesn't even register~ if they are not approved by their leader/fellow followers, much in the same way 'god' doesn't register for atheists.
For religious leaders, all that matters is that their followers continue to focus on them for education, reward and punishment; one could even argue that the content of the doctrine used to establish/maintain this dependancy system... isn't even important.