Comment 2 for bug 215662

Actually, if you look at the docs preview site as a tree, the "leaves" don't have such links. An example:
http://doc.ubuntu.com/ubuntu/about-ubuntu/C/about-linux.html

Such documents are most likely to contain the actual documentation (rather than ToCs) and be linked to or be the origin of derived contents.

Maybe just adjusting the web template (footer ?) would be enough to make sure every single page has that information (just as the wiki does).