What's their success rate like, I wonder? It strikes me that anyone vulnerable to this sort of thing would have succumbed years ago, and then would sell out to the Mormons and so on as each came round in turn. If their success rate truly is zero, WHY DO THEY WASTE EVERYBODY'S TIME DOING IT!?
I've often wondered about that myself, Simons Mith. After all, if my forebears are to be believed, even the tramps used have a 'secret' code which they scribed before someone's dwelling to indicate 'Probable', 'Possible', 'Unlikely' and 'Don't go in there the dog will eat your balls and dump your remains in the bin'. Then again, most tramps are probably better organised (and intelligent?) than those of whom we speak.
I live in a student house, and it was a student house for many years previous. I think they've learnt that we have absolutely NO surplus money - it all goes to tescos or over the bar. and I generally tell jehovah's witnesses I'm jewish. gets rid of them.