Just exactly that, really.
Following today's 'have you heard the good news?' doorstep visit, I've been wondering what the conversion rate actually is, and I cannot think of any way in which it could be a successful strategy for drawing people to your religion, unless they were particularly vulnerable.
So, what I'm wondering is: has anyone ever answered the door to a total stranger, listened to what they have to say on spiritual matters, and subsequently seen the light?