I find it annoying when users are explicitly instructed to use the Back button to navigate away from a webpage. An example from the login page for the Contensive CMS follows (emphasis added):
The content on this web site is managed and delivered by the Contensive Site Management Server. If you do not have member access, please use your back button to return to the public area.
This wording can be condescending to experienced users who know how to navigate away from a page, because the user is given specific instructions to perform a very simple operation. Is it necessary to specifically instruct users to use the Back button to do so rather than simply instruct users to simply go back or otherwise leave the page (without explicitly mentioning the Back button)? What advantage does telling the user what control to use (such as the Back button) bring in relatively simple interfaces such as Web browsers? What alternative wording can be used to instruct a user to navigate away from a webpage?
Note that this question is not limited to site administration pages. I've seen such messages in pages where a specific piece of content (such as a picture) is displayed; the user is told to click Back to exit the page once the user has finished viewing it.