Why is something that can be called as a sub rather than a method not OO in any meaningful way? Subs are not attached to a data structure. Subs don't support inheritance. Subs don't support polymorphism (aka "late binding").

Yes, of course. I'm not confused on the definitions, differences, or their uses. I was just pointing out that in this case we clearly have an example of a sub/method "wearing both hats", possible only because of the flexibility of Perl. (as an aside, this convergence is far more likely with constructors, when you instantiate and bind your methods to a particular set of data, as opposed to just random methods -- such is the case with Time::Piece, where contruction happens either via new(), overloaded math operators, gmtime(), or localtime() -- this last two are procedural subs, but underneath they all use a constructor that does double duty as a method or sub: _mktime())

As I said, it's not a particularly good idea -- it just sounded like you were asserting that since there was a second hat involved, the first hat no longer applied. I apologize if that was not the intent of your statement.

Matt