Had a user who spent considerable time editing a new blog entry, but unfortunately put an illegal character into the title. When he went to preview the blog, a new page displayed an error indicating the illegal characters and advised user to return to previous page to change title. However, on hitting Back button user gets new, blank edits page. His content was gone. WBNI this worked like regular pages where you simply get the red error displayed on the edits page and you are not redirected away from your edits page.