If I correctly understand the distinction you're making between "untestable" and "meaningless", then the hypothesis "God rewards Christians with Heaven and everyone else goes to Hell" is untestable but not meaningless, correct?

Yes, that's right. But in the evpsych context almost all hypotheses are at least meaningful, so we're drifting off the issue.

If you were unsure of evpsych story X, and you found a way to test it, would your probability for X go up? It shouldn't, and that's all I'm saying. The possibility of future evidence is not evidence.