Overloaded methods share the same name but different signatures and have no polymorphic relationship. Overridden methods share the same signature and are replaced at runtime in all places it is defined. Hidden methods are share the same signature but are only replaced in the subclasses for which they are defined.
From page 263
... hidden methods only replace parent methods in the calls defined in the child class.
Alternatively, at runtime the parent version of a hidden method is always executed if the call to the method is defined in the parent class.
I don't understand the context to the place where a hidden method is called. Can someone give an example?