Some writers' syntax is so distinguishable that you can recognize the writer by the way the words have been arranged. I would imagine psycholinguists eyeball closely syntactical habits of writers under investigation. And these psycholinguists would be on call by the FBI to try to determine authorship.

Once someone wrote to me under an assumed name, but I had a strong gut feeling of the author--and I was correct--simply because of syntax. Some people's syntax is positively seductive--no joke.

Best regards,
WordWonderer