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+The core idea around the security design is to build for multiple authorization
+levels. The core reason, surprisingly, is for easy caching. One of the ways that
+many existing forums have some users invalidate a lot of caches is that they
+serve up special content for moderators at the same URLs that normal users use.
+This means more cache misses, intrinsically.
+
+To avoid this, and to improve security, functionality should be locked at
+multiple security levels, so that normal moderator browsing can have some
+additional features, but generally ones that can be added through loading some
+additional resources, not modifying the existing page.