Why should we ever consider invention on a different level than (re-)discovery?
More concretely: if the "Goldberg-Variationen" had grown on trees instead of being written down by Johann Sebastian Bach, would the light they emit lose its value because of this? Or vice versa: if the opera omnia of Nino d'Angelo were one day attributed to Leonardo da Vinci, would it stop provoking defecations because of this?
Yes, I know. These are sterile bar chats. I agree; except for one detail: the role that authorship — invention, originality, genius: all terms that make your skin crawl — plays (even just lexically) in singer-songwriter music.
Now, is it possible to consider "singer-songwriter music" as one in which songs are not invented but rediscovered?
If the answer is no, I'm sorry for you.
If the answer is yes, listen to Caterina Bueno.