Insofar as scientists have disproved dozens of theories for why certain things happen, I don't see a reason why scientists wouldn't be able to conclude that god was doing the orphan thing.
In the same way as scientists could conclude that God is directly responsible for the strong nuclear force?
While I don't deny that it could be advanced as a theory, I don't see how it could be tested. And I don't see a theory gaining much traction unless it can make falsifiable predictions.
Plus it'd probably be a big tip-off that the only holy book with no factual errors also mentioned the orphans being fireproof thing.
If orphans really were fireproof, I'd expect it to be mentioned, at least in passing, in most holy books. Mainly because orphans being fireproof is something that people will tend to notice.
While I don't deny that it could be advanced as a theory, I don't see how it could be tested.
If your hypothesis cannot be tested, then why does it even matter whether it's true or false ? Since you cannot -- by definition -- ever find out whether it is true, what's the point in believing or disbelieving in it ?
To put it another way, what's the difference between believing in a god who is so subtle that all of his actions are completely indistinguishable from inaction; and in not believing in any gods at all ?
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.