BUT you can still view the U2U page by clicking on one of the U2U buttons in a thread when you are not logged in - it just gives you an error message telling you that you must be logged in.
All the board does is replaces anyone looking at the U2U page with "SECRET" instead.
Not that it matters one iota, but a colleague who was browsing this site on recommendation from yours truly, clicked on the ----SECRET---- in the who's online section, guess what.....it took them directly to whatever the user was browsing, so it wasn't a secret after all. (in this case it brought up the results of a search item).