In social settings with people and kids Gunnar still believes himself to be alpha when confronted by strangers. And people being dumb like to pet puppies without asking and sometimes get nipped by him. But what I've noticed is that he reacts to being petted on the head just like the alpha dogs at the park react when Gunnar puts his paw on their heads. If people pet Gunnar on his back or sides he does not get as riled up.
If I may.....I wish you'd re-consider your pup's reaction as being dominate or Alpha. He's a puppy. A baby. Think of it as your pup is confident. A confident pup. A great thing to have.
A four month old pup is not ever allowed to react towards a stranger or anybody by nipping. Play or not. Ever. A stranger should be able to handle your pup anywhere on it's body with out any negative reaction from your pup. It's up to YOU to decide if a person can pet your pup...not your pup. Not ever your pup.
My 3 year old 97lb male GSD is a confident, aloof dog. He doesn't like to be pet by strangers. He doesn't like for strangers to bend over him. But if they do, by God, he will NOT
react. He'll look at me. My job is to respect his needs and not put him in a situation where he has to give me that look.
As a puppy, while I was socializeing him, I noticed when strangers got all goo-goey over a puppy, he'd ignore them. Didn't matter what they said, or how they called. He'd ignore them. If they came to him to pet him, he'd ignore them. He allowed them to pet him and gush, but he didn't respond. That was a clue to ME
that to have people gush over him just wasn't his bag. My job was to teach him to allow it, without reaction.
I can take my dog anywhere and know that I can control him. If I had allowed him to progress and react, he'd be stuck for life in my back yard with a high insurance policy.