I feel that this discussion is getting a bit too multifarious, which no doubt has to do with the very abstract nature of my post. I'm not very happy with it. I should probably have started with more comprehensive and clear examples than an abstract and general discussion like this. Anyway, I do intend to give more examples of reverse-engineering-of-belief-structures-examples in the future. Hopefully that'll make it clearer what I'm trying to do. Here's one example of reverse engineering-reasoning I've already given.

I agree that lots of the time we should "do a bit of digging ourselves"; i.e. look at the direct evidence for P rather than on whether those telling us P or not-P are reliable or not. But I also claim that in many cases deference is extremely cost-efficient and useful. You seem to agree with this - good.

...but there is a distinction to be made between using online behavior to measure/understand the general population's belief structure and to check for bias in expert opinions.

Sure. But reverse engineering reasoning can also be used to infer expert bias (as shown in this post).

To some extent, this is how it's already been done historically, but it was not done via raw data analysis.

Yes. People already perform this kind of reverse engineering reasoning, as I said (cf my reference to Marx). What I want to do is to do it more systematically and efficiently.