[thdc]

Yeah around 1.5mb transferred but less of an issue with caching of course.

You also won't have something nice like $$ or \[ \] and will have to put the

    <script type="text/tikz">
        \begin{tikzpicture}
            ...
        \end{tikzpicture}
    </script>

tags directly in your markdown, if that even works.

[ajkjk]

Jekyll at least has an <% include %> tag that can introduce html into a markdown document, so I can probably use that. Tbd. The $$ is awkward though.