I personally see it as a source of ambiguity and difficult to predict bugs. What if you define return() within a package, to be used as an object method, but then within the class itself one of the subs uses return()? Which return() will be called, the package one, or the core one? I had to test to find out (in my simple test, the core routine got called). I see it as an unnecessary source of potential mistakes.

Perhaps a :method attribute would help. To quote from the docs:

method
    Indicates that the referenced subroutine is a method. This has a
    meaning when taken together with the locked attribute, as describe
+d
    there. It also means that a subroutine so marked will not trigger
    the "Ambiguous call resolved as CORE::%s" warning.
[download]