The CommentPlugin lets you hide parts of a Wiki page without actually deleting the text. Comments will only be visible in the Wiki markup when editing or viewing the source.
Simply place the text to be commented out between <?plugin Comment= and =?>:
<?plugin Comment !!! A Hidden Section This text will not show up in the generated HTML page, but it is still visible when editing the WikiMarkup. ?>
Martin Geisler 
gimpster@gimpster.com.
The content of this page is Copyright (C) 2000, 2001, 2002 Geoffrey T. Dairiki and
the other authors of the content, whoever they may be.
This is free information and you are welcome redistribute it
under certain conditions; see
http://www.dairiki.org/HammondWiki/opl.html for details.
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the information on this page.