Just like you don't duplicate the signatures, it would be useful to detect if the text begins with a section title and drop the warning about adding a title.
Topic on Talk:Talk pages project/Replying/Flow
Are you thinking of the editors who edit an existing ==Section==, and then create a new section (with the old section's name in the edit summary)?
No, I don't think your scenario would get you that warning. I am thinking about users using the new section link then either:
- copy-paste a section, including section title
- substitute a warning template which contains a section title, such as ro:Template:au-test1
Both cases will have a warning appear, which urges the user to include a section title. The warning will only go away if something is introduced in the title field.