@Misadventure -- You could arguably code watch to handle unknown alts in the way I described without revealing them in the process: when you do +watch/hidefrom <name> (or whatever one names the command), <name> is added to your list of people you're hiding from that you can see. The actual list the +watch code references, however, can be stored on an attribute that isn't player-visible. This means it's possible to, when adding Sally Chatterbox to your 'hide from' list, have the code also IP check Sally and add her and her alts to the list the code is actually using to hide you -- not your little list of names that you can see. This way, you can hide from a player engaging in annoying player behavior without revealing that player's alts and infringing on their privacy in the process.
To the best of my knowledge, this code doesn't omit them from the list of connected watched people when it's randomly checked -- it just doesn't alert you directly when they connect or disconnect. Which is no big deal, IMHO.
+watch isn't overkill. Pagelocking someone for being a minor nuisance in regard to the way they use +watch kinda is.
TR had a pretty nice setup generally for +watch compared to others I've seen. You could selectively hide from individual charbits with it -- which is helpful. I never was a fan of Shang's 'all or nothing' approach on this one, for instance.