However, the person who posted the comment also has the ability to delete it - the question is, how do we find out if the viewer is that person? Should viewer_is_owner() really be checking the owner of the entry, or the owner of the comment? (Since this is happening in the comment.print function.)
viewer_is_owner() : bool Returns true if the user viewing the page is both logged in, and is the owner of the content in question. Useful for returning links to manage information, or edit entries.