Creating common grounds for (productive) discussion with the entrenched and indoctrinated.

I read a post on the RichardDawkins.net discussion board today entitled "Another Family Destroyed by Religion." I have also personally witnessed two separate incidents of families becoming absolutely broken apart by the JWs. It struck me that it is obvious to we who lack the reality-distorting paradigm of religion that the act of parents disowning and abandoning their children for the mere fact that they reject a single belief is appalling, while to the ones inside the religion it is rationalized into being seen as a just and necessary act--hell, they'll even call it "divinely ordained."

This leads me to wonder how we can bridge this gap with believers and get them to look at their beliefs objectively. We can spend all day creating dialogue, and that is a great way to start, but in my experience, it often doesn't matter in the end what amount of evidence you have, how perfectly you refute their every argument, or how clearly you explain the fallacy of their thinking: a dyed-in-the-wool theist will simply resort to a vague, subjective sense of confidence in their beliefs and say, "I can feel it in my heart, and it doesn't matter what anyone says because I believe it on faith." In other words, the information presented is made arbitrary by the believer's indomitable bias for their beliefs. So how do we get them to realize and acknowledge this bias for what it is?

The more debate and discussion I take part in, the more I come to believe that nearly every argument for the existence of god has become a PRATT (previously refuted a thousand times), so much so that it is almost a waste of time to keep giving our time and attention to specific arguments for god--*there are no good arguments*. The time has come to criticize faith itself. We need to stand up as a community and tell the world why faith is unreasonable, unnecessary and inferior as a means of inquiry. 

I applaud Jerry Coyne for taking a firm stand on the subject in his recent article, "Science and religion aren't friends." EbonMuse has taken the different and directly engaging approach of describing what kind of evidence he would require in order to believe in god and, in return, asking any willing theists to explain what evidence they would need before they gave up their belief. In nine years, he has gotten six takers.

So my question(s) is this:

How do we best state the case against faith in a way that will lead believers to a common, rational grounds for productive discussion while not sounding derogatory or condescending? How do we get them to see faith for the simple unfounded bias that it is? How do we get them to question their belief and think critically?