[gnoack]

The way I interpreted most of these "subclassing" cases in the GoF diagrams was actually as "subtyping", and then it makes more sense.

Regarding no one having a lock on the term "delegation", I think this is spot on. Yes, someone might have used the term differently before GoF, but that does not mean that GoF was wrong. It just meant something else in their context.

(Btw, congratulations, your comment is the first one so far in this comment thread that actually discusses the linked article and not just the GoF book itself.)