My own conclusion is therefore that, at least for now, one would have to
squeeze the Elyxer output into a template that takes care of all the site
integration. This template would then have a get-me-out-of-here link, or a
more elaborate form of site integration.
I think the template is an excellent solution; as you will probably
know there is even the --template option to help with this.
Having said all this, José Ramón's suggestion of the --uplink would actually
make sense. However, instead of redefining the Up: link on the first page,
it could be a little header (or footer) in it's own right, sitting above the
page nav header and below the page nav footer of ALL pages. --uplink would
require two string args: the visible text, and the url:
--uplink "Go back to documentation index" "../../docs/index.html"
Not that José Ramón's suggestion doesn't have merits, of course; but
one must ponder the benefits against the costs. In this case it looks
too complex when a template is probably a better solution anyway.