Earlier quoted context omitted.
It's not the author's fault, directly – it's a problem with the platform (syrah.co). I upped the font-weight from 300 to 400 in Chrome dev tools, and everything was instantly better.
I'm the author of the post and I wrote the entire site's codebase (syrah.co), and I did all the design, so it's all on me. You're right, we will be fixing this in an update soon. Syrah is still in beta and we weren't quite expecting this to get as widely read as it's becoming, so hopefully you'll forgive the crappy formatting :) Appreciate the feedback.
EDIT: I was under the presumption that reader view used RSS, which it turns out it may not. Anyway, very good article with a lot of good facts, forgot to mention that in my slight rant about styling on the web above :)