Hey Deranged,
This is a concept that is also at play when Hero is in position with a decent hand and villain randomly donks the river. Since he usually has either a really good hand or a complete bluff, there is often not much reason to raise.
Maybe an example?
By the way, I can't remember who it was, but somebody used to talk about this concept quite a bit (I think maybe Joe Tall?). Anyway, it's something that I think is quite applicable to many river decisions.
Good post.