I love this sort of static generator for a non-obvious (perhaps) reason: you can version control the source. I find that hugely useful when maintaining a complex site.

I wrote a similar tool, years and years ago, that took what looked like "troff -ms" input and spit out the whole website, complete with a site map. Here's an example

http://www.mcvoy.com/lm/bkdocs/UG/tmp/Introduction.html

if you go up a directory level and poke around, that's the source to website and webroff is the script that produced that website.