Hazlo on "[Plugin: Autoptimize] Should caches be disallowed with a robots.text?"

Hello Frank
My question is about the relationship between caches and Google indexation.
I have a cache folder on my server with both Lite cache and Autoptimize caches inside.
And I wonder if I should disallow this folder with the robots.text or not.
If i don't, is there a duplicate content risk?
And if I do... will my posts and pages still be indexed properly?
It's quite important to be sure with this point I guess!
Thanks in advance for your advice, and also, of course, for your very good plugin.

http://wordpress.org/extend/plugins/autoptimize/