At the moment, I have markdown files that need to be styled with foo.css. I run the command:

$ pandoc -f markdown -t html --css foo.css --standalone --self-contained bar.md > bar.html

This does work, but it embeds the CSS as a massive data URI included with a link tag, which prevents certain optimizations from occurring outside of pandoc. Instead, foo.css should be placed verbatim (or minified) into a <style> tag, avoiding the data URI entirely.

To work around this bug, I currently use:

$ echo "<style>" > /tmp/open && echo "</style>" > /tmp/close
$ pandoc -f markdown -t html -H /tmp/open -H foo.css -H /tmp/close --standalone --self-contained bar.md > bar.html

This works as expected, but it is decidedly messier than it needs to be.

For text formats (as opposed to self-contained images and the like), is there a good reason to use data URIs?