Though there is sometimes point in exit()ing after it. There's a fairly well known attack which involves client-side trickery to avoid following a refresh, because sometimes (i.e. in very poorly written code) you'll get a valid page of data instead of, for instance, the redirected login page you should have got.

Hi monks, I've taken up CGI recently

... I'm not sure that's something you admit to in public... (kidding)