-well covered by existing mirrors. Please don't bother asking us for
-permission before setting up a mirror. You already have permission. We
-are always happy to have more mirrors.
+well covered by existing mirrors. (However, if you're in a region that is
+already well served by mirrors, you should consider whether yet another one
+will be worth the effort.) Please don't bother asking us for permission before
+setting up a mirror. You already have permission.