Toadinthehole at least disagree with what he was actually talking about. Saying that in order for that situation to arise we'd have to live in a police state is missing the point.
If I said "suppose you were on a south sea island now and lying on the beach" you wouldn't say "ha! so I've been kidnapped have I?"
The claim is one that is pretty much common sense. That if - for any reason - children didn't learn about god until they were old enough to think for themselves, that religion wouldn't have the same hold.
The point being that the reason religious people and organisations are so obsessed with teaching them young is that it won't work right if they are old enough to think.
The evidence includes speeches by representatives of all the major churches. When they argue to keep compulsory worship they all claim that to not do so would damage the church and leave it with a rapidly decreasing membership.
Of course you can talk some adults into converting, but it's nowhere near as effective and imagine bringing it up to an 18yo ir even 14yo who'd never heard of it.
"ok so.. There was this man right and he was killed, but he was alive again and anyway he was never dead because he is in heaven the whole time and like you can't see him, but...
... and yeah if you do what I say you will go to heaven and be perfectly happy. if your mum and dad don't then they can just suffer for eternity. Don't worry you won't care about them any more once you're in heaven "
That's why they have to be told at the same age they are told about Santa.