This is where Dave Winer narrates his development work.
These two bits are set in html.directory.viewDirectory, which assumes that pages that take full control of their HTML would never want to say where they are relative to other pages. But what if you wanted to put a crumb trail on a howto node? You're out of luck.
So we have to move this code out of html.directory.viewDirectory. Possibly into a new html.directory routine just for this purpose, to set all pre-rendering atts that depend on the location of the page within the directory hierarchy.