ChatGPT assures me it doesn't use RAG (fed from my other chat windows), but will use memory-saved preferences (in the store that can be accessed and reviewed in Settings->Personalization->Memory).
Then again, I don't think ChatGPT is reliable when reporting on its own inner workings.
It seems like a good approach though. What you dont want to do is ever suggest that its wrong yourself. Usually it will just assume it is wrong.
Actually what I find impressive is when I do this and it actually pushes back to defend itself.