Ok, that's reasonable.
If you want to learn more about it there is considerable information here http://yui.github.io/yuicompressor/. Even though most Autoptimize users probably haven't understood its advantages or exactly how to enable it, the YUI Compressor is actually very easy to install and use with Autoptimize, especially under Linux. It is equally easy to install and works just as well under Windows, but a few simple modifications are needed to Autoptimize to make it compatible with the YUI Compressor under Windows.
Some WordPress plugins that fail using the PHP compression code in Autoptimize run fine using the external YUI Compressor.