Yeah, I had some promising results in a project that split markdown-based docs by second-level headers, embedding them all, and then doing basic RAG with GPT-4 serving a response. It was too slow at the time (June last year) but I'll probably pick it back up again this year.

The main things I took away were (1) if the information archictecture isn't very splittable, this gets too hard, and (2) always link back to source information.