I did something very much like this for a while. I'd use WordPress to create content on my laptop, then I'd crawl my own site using wget to collect the results and push those up to the real website. Turns out there are a few gotchas that simply-static didn't address, but I wrote a blog post about my experiences here.
http://pl.atyp.us/wordpress/index.php/2013/04/using-wordpres...
The older posts on my site were all converted this way, though the newer ones are done directly in Pelican.