I'd be happy to work on making an 'idledoc' target for the Doc/ makefiles that works with Mark's viewer. I can't guarantee any kind of timeframe, but the idledoc target wouldn't be necessary right off the bat; it could be done after the main bulk of the patch is committed.
As far as reST comments, the syntax is:
"""
.. This is a comment.
This is still the same comment.
And more of the same comment.
This is no longer part of the comment
"""
See http://docutils.sourceforge.net/docs/user/rst/quickref.html#comments