I've been playing with their ruby-kit, so far so good, really liking this approach and plan to see awesome things ahead.
Prismic allows you to "go static" for very little dev cost. Your content creators get a nice editor and can publish their content as needed, effectively making it static for you (the dev), as though it went through a build script (Jekyll or something "static"). The CMS gets out of your way, and you get to concentrate on making your app work, not getting into the complexities of building/maintaining a custom CMS.
I mean, that's what the assertion that static is the way to go eludes to, unless I am incorrect about the entire point of the article. It's about not getting dragged into the bog of making a CMS.
The author outlines various scenarios: do it yourself, to building your complex app on a CMS (ugh), or just going back to static because it is the simplest, hardest to fuck up option. I don't think he explored the idea of content management as a service fully, which is why I brought up Prismic—it is another option, and in my opinion, a very good one.
So it worked for me as a editor gone code-writer as well as a editor gone conceptual project-lead.