Overall, I again feel like I should apologize; I am using a pseudo-scientific attitude to build my reasons for disagreeing with you.

Basically, I think twe should make a distinction between:

1. Confirmed sources, by the author, or by other people close to him.

2. Likely sources, for which we find evidence within the written work, like, say matching character and location names, direct or indirect quotes, etc.)

3. Possible sources, which we consider likely, but have no hard evidence for.

As to the lists in concrete, I'll try to put up omething tomorrow. :)