>>The Wiki will be an online version of a printed handbook. Users should
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>>be able to 'comment' to pages, e. g. ask questions, discuss issues, ...
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>>These comments must not be part of the WikiPage. The handbook's content
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>>must not be altered when commenting.
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Why not have the handbook as static (normal nonWiki) pages, which in the
footer has a link to comment on this page. This link then takes the user
to a wiki site, and the appropriate page for commenting on the
particular page. If you don't want the handbook editable, don't put it
in the wiki.