I agree fully with the poster(s) who said it's the owner. I've known a few doverman (sp?), one of them I knew quite well was a good dog and very affectionate to his owner but very easily frightened... so I could never make sudden movements with him..

Unfortunately I've had two dogs on both sides of me who were beaten by owners (past / present). one was german sheppard one was a unknown breed. The other one would sneak up to you and try and nip your wrist when back was turned.
on a sad note both dogs were put down, all because of their prior experience with owners and couldn't be re-trained.
If the dogs had better owners or training I'm fully convinced that they would be different dogs.