Most of the features implemented in Amazing Stuff 4 have also been implemented here, but there are a few changes to note: 

There is no POST_SAVE, so the browser will not remember an invalid form submission.
This should mostly be OK, however, since most of the form validation takes place clientside, and the only form issue that
slips by the clientside validation but not the serverside validation is a duplicate email. 

The "depersonalization" of the header occurs one link after the actual logout. 
This is because the session_start() call is placed in the page header rather than on the top of every single page, and
the logout code to destroy the session is called after the page header, so that it can print different output depending on whether the
user was logged in when they tried to log out.