I think you are asking that the template pay no attention to notes. Instead it takes a set of books and reduces that set to one book per author.
If true, then this pseudo search would do the same as the original template:
Code:
search:has_author_notes and search:one_book_per_author
You could also do things like
Code:
not tag:foobar and search:one_book_per_author
producing a list of one book per author where the books don't have the foobar tag.
Do I have this right?