Over engineering is a form of bad engineering, at least in my book. Fun starts when some parts of a product are over engineered while others are under engineered... One of the cases good averages get you nowhere...
I think nearly everyone would agree that "over == bad" in most settings, but the reverse is being implied by the GP - that bad engineering is a form of over engineering.
No tests? Nobody knows how it works? It doesn't perform well and doesn't fit the problem it's solving? That's very much not over engineered in my book.
