Correct. Internet posts contain explanations, if at all, rather than reasoning, which is not the right model for LLMs because it starts with the conclusion and

Correct. Internet posts contain explanations, if at all, rather than reasoning, which is not the right model for LLMs because it starts with the conclusion and then describes in hindsight the steps that have already been taken, invisibly, to reach it. It's a retrospective trace of our own chain of thought, not the chain of thought in itself. We can only write explanations because our actual reasoning is, invisibly, present in our mental context window. But that's exactly the tokens that would actually help a LLM. (That's also why we can explain answers backwards as easily as forwards.)