Just another "why is it that way" question: I noticed that private helper methods still can be accessed within views. Why's that? And is there a way to prevent this (e.g. when having helper methods that should only be called from within another helper)?
Helpers are modules that get mixed in to the views. This means that public, protected and private methods in the helper become public, protected and private methods on the views.
I don't think that you can actually hide the helper methods from the view. You'd need to do something like have a helper class which you instantiate in the helper and then delegate calls to that - sounds like it could get messy fast though. :)