To me, the main reason to avoid obscurity in naming or numbering things, or even in code - rather than view it as a modest addendum to security - is to force yo

To me, the main reason to avoid obscurity in naming or numbering things, or even in code - rather than view it as a modest addendum to security - is to force yourself to do the mental exercise of what happens when that obscurity is lost. Not doing that is how small companies seem to get away with terrible security holes for a long time, until suddenly they don't. I've seen too many cases of companies in a position where they built a small, insecure service that's now getting shared more widely than envisioned, who don't want to spend the money to make it right, because no one has compromised it yet (that they know of), and what are the chances of someone stumbling across it - where even pointing out that it's an attack vector can earn you trouble.