Neal,
you may simply forget about all the weird Apache stuff and sort of concentrate on the non SSL and caching options. Apache serves static pages for our website and listens on port 80, therefore the need for reverse proxying.
It takes about 1-2 seconds to load the iNotes pages (mail, contacts, todo, ...) served by Dominos HTTP task *after* they have been loaded the first time and cached locally.
If you add response header rules and use the key word "Public", the local browsers cache and proxies in between will be able to cache content (images, Stylesheets, JS libraries, *a lot* of layers, etc.). The iNotes Javascript routines kind of reload the actual "information" (see the message "Fetching records ...") every time, which makes it so easy to implement an effective caching technique. Caching is useful for other non iNotes pages as well, but much more difficult with forms, documents and especially views in other LN databases.
The following links may be of interest:
http://www.ircache.net/cgi-bin/cacheability.py
http://www-10.lotus.com/ldd/today.nsf/62f62847467a8f78052568a80055b380/2aa6ecf8f295019085256b9c006fd147?OpenDocument&Highlight=0,caching
Good luck,
Uli