I agree with the value of a non-null example and think this is a very fine piece of documentation. 2 reasons I'd hold off for now:

1) We plan to flip the bit for edx.org soon after merge, so the settings files will change and give us a non-null example. For now I'm focused on making sure the semantics and capabilities for settings are right and I'm less concerned about the exact state of the settings files given that they're going to change.

2) I think that the authoritative explanation for loading auth settings should go in `common/djangoapps/auth/settings.py`, and that we should point to it wherever else it's relevant. Otherwise if we make changes we run the risk of missing documentation sites like this, leading to confusion. Do you think the docs in `common/djangoapps/auth/settings.py` are sufficient? If not I'd love to improve them.