It's pretty easy if you're using customizable menus to forget that you customized that, and direct somebody at an option/location that doesn't exist in their screen (we already get this with the different site schemes).

Also, logged-in homepage has the advantage over Links in that nobody else is 'bothered' by seeing it. On the Gripping Hand, I don't know how expensive it would be for the server to track that certain of your sidebar links were 'Private' and only load them for you. Then you'd see it whenever you were in your journal...