The characters - DramaticIdentitys - may have signatures, although they do not need to be Wiki page names. If there are only 2, one may be written in normal text and the other in italic.
Dialectic Mode has the advantage of Thread Mode that it is easy to express the to and fro of ideas, thesis and antithesis. It's easier to refactor from Thread Mode because most of the dialog will be written in first person. It also has the advantage of Document Mode of being less ego-laden and thus easier for third parties to edit.