CakePHP Questions

I'm working on coding up a nice interface for adding/removing ACOs, and granting/revoking permissions on them for the AROs in my database. I have a functioning system, but it definitely could use some polishing.

With that context in mind, what is the use of the AcoAction model? I see it in the API but it isn't covered anywhere in the manual. Is this really just sort of a "helper" model that is inherited by other built-in ACL models, or is this something that can actually be useful for using directly? Looking at the API, it seems like every method is inherited, so it makes me wonder what the class is even used for if it doesn't have any new methods it implements itself.

Anyway, I was curious, since given the name, it would seem like a class that handles manipulation of action-specific ACOs.