Even as a programmer, I've fallen into the static site generator trap a few times.
It's annoying to start a side project with a static site generator and then realise I want to add a small feature and suddenly I wish I'd just started with a simple Rails or PHP app.
Nowadays, if I want a static site I just start with a folder of html files. It's way less complicated and quicker to go from idea -> execution without bike-shedding or procrastination on tools.
I'm pretty happy writing html and css manually though—I don't recommend it for everyone.
The other cool thing is if I then decide to "abort" to rails.. I can copy the folder of html files into the rails public/ folder.. pretty easy upgrade path.