I mean, if we dig around in a dog's food dish, and take shtuff away from the dog, and mess with it and give it back, we can create food aggressive issues where there might not have been any. Can we also create problems by pushing a dog to accept everything from everybody as a part of socialization, and if the dog doesn't seem to like it, flood the dog. When if we had left well enough alone, the one or two incidents that might happen when someone the dog does not trust gets into the dog's face, the dog will be startled/surprised, but not actually aggress to the point of a bite.
Everyone's training methods are different and I know most here are horrified at the way I train. But I do get down on the floor with the pup. Right in his face and his in mine. I also pick him up and cuddle him to my face. I touch his paws, his ears, his tail and look in his mouth everyday! But then again I also put my hands in his food bowl pick up food and hand feed. My adult dogs (the one's I've raised) will let me take anything away from them and they will tolerate a lot of in your face from people. That being said I also think a lot of it is genetic. Buddy is bomb proof. He is absolutely rock solid and has proven it time and time again. Ivan is skittish. I got him from the shelter, he is a mix of lab and god knows what. I don't know what happened before I got him but I think if a stranger got in his face the way I do, they might get bitten so I don't let strangers get in his face.