Interesting question. I'm reading a book now that has me asking related questions about the medical field. I think they make a good analogy.

Until a couple hundred years ago, medicine was based on the theory of the four humors. Blood, phlegm, yellow bile and black bile. And that all illness was the result of an imbalance of humors.

It was made up. It was wrong. It didn't cure the sick. But it did do one thing. It made predictions that could (and eventually were) disproved. All truths must be falsifiable. Making things up when you don't know is otherwise called formulating a hypotheses. It's a logically sound approach.

The thing is, the God hypotheses hasn't yet been disproven.