I'm of a bit of a mixed mind on this. On the one hand from a purely tactical point of view this is very useful. Ex-preachers are an excellent bulwark against the "you're only an atheist because you don't understand theology" bullshit like of argument, and getting a preacher to come out can affect more than one person because it can make their "flock" think twice about the next preacher they hear who, on the surface, seems just as certain as the one that lost the faith seemed.

But on the other hand I just don't have as much sympathy for their personal situation as I'm being told I should have. If you've gone through the schooling to be a proper preacher - if you're very well informed about the bible and its history - then your decision to spread the word anyway is more than mere delusion or gullibility - its deliberate deception. Every preacher who studies that evil book and pretends it's all sweetness and light is outright lying to his flock, and does NOT have the excuse of ignorance.

I support this ONLY because of its efficacy, NOT because of any sympathy for those who chose, on purpose, a career of deception.