Earlier quoted context omitted.
like OP originally said, the LLM doesn't have access to the actual process of the author, only the completed/refined output. Not sure why you need a concrete example to "test", but just think about the fact that the LLM has no idea how a writer brainstorms, re-iterates on their work, or even comes up with the ideas in the first place.
i don't buy this logic. if i have studied an author greatly i will be able to recognise patterns and be able to write like them. ex: i read a lot of shakespeare, understand patterns, understand where he came from, his biography and i will be able to write like him. why is it different for an LLM? i again don't get what the point is?
The point is that you dont become Jimi Hendrix or Eric Clapton even if you spend 20 years playing on a cover band. You can play the style, sound like but you wont create their next album.
Not being Jimi Hendrix or Eric Clapton is the context you are missing. LLMs are Cover Bands...