The sidebar, permanently-fixed and consuming more than half of the screen, makes this blog completely and utterly unusable on a mobile device - that is, unless you're attempting to find the author's twitter or send him an e-mail.

EDIT: Additionally, this concept is already implemented rather well via various[0][1][2] browser extensions.

[0]: https://addons.mozilla.org/en-US/firefox/addon/ui-enhancer

[1]: https://chrome.google.com/webstore/detail/breadcrumb-navigat...

[2]: https://addons.mozilla.org/en-US/firefox/addon/locationbar²-...