Originally Posted by Mary Beth
A dog's distance vision is actually poor compared to humans, so it could be that Diesel is not sure who the person is (friend or foe) which is why he crouches and waits until the person gets closer and then realizes the person is a friend. I would still be careful and be sure to greet the person as he comes up so Diesel knows he that you have seen the person and it is okay.
THis is kind of my thought, he has never tried to be protective or acted in any type of aggressive manner with a human but it kind of threw me off the first time it happened then I started to pay attention the second time and third time I realized there is something going on. I dont "think" he would bite someone but I know my one friend is terrified of him, says she does not like GSD because unlike other breeds they are not easy to read their expression is always the same which I kind of agree with but I am not afraid of them (clearly lol!). He is normally pretty "bouncy" so for him to get so quiet and lay down like that just tells me he is uncertain of something.