The mental hurdle people seem to have is accepting that the dog decides what is spooky or threatening. This is a dangerous place to be anthropomorphic.

I have to confess that I'm really not understanding what this quote means. Perhaps its because its out of context.

Can anyone explain what the danger is... and to whom... The dog, or the person?

Just curious.

It is a bit confusing........Perhaps dangerous because human thinks they know what is scary for the dog. But in actual fact only the dog knows that.

Exactly. 

While I think the observation stands alone, this author’s context is often that dogs so often pay with their lives for failing to live up to some fairy tale idea of how dogs are or should be.