It'd be nice if the mtime of the files ikiwiki renders matched the mtime of
the source files.

However, this turns out to be more complex than just calling utime() a few
times. If a page inlines other, younger pages, then having an older mtime
means that an old version of it will be kept in web caches, forcing
annoying shift-reloads to see the changed content (for example).

And it's not just inline. The template plugin means that a change to a
template can result in changes to how a page gets rendered. The version
plugin changes page content without any younger page being involved. And
editing one of the html templates and rebuilding the wiki can change every
page. All of these need to be reflected in the file mtime to avoid caching
problems.
