Good range of options

well, Autoptimize is a CSS/ JS optimization plugin, not a page caching plugin @swinggraphics ??

from the description:
<blockquote<If you consider performance important, you really should use one of the many caching plugins to do page caching.

so combine AO with a page cache (WPFC is a good one, simply disable the minification features in it) and you should have a better idea of how AO works. you could then take it a step further (faster) as described in this blogpost.

hope this clarifies,
frank

Updated

thanks for that @swinggraphics!