Sure I also answer to the redirected aggression situation and don’t see it as a play. To have a dog not biting you - you gotta break down tasks into smaller tasks. One is reactivity towards the dog. Fear etc. Another is redirection. Third is how dog treats human. One task is to teach your dog not to take your body into his mouth and if it happens not to squeeze hard. You do it in training with various ways. So dog gets a hang of it and then during stress times doesn’t turn to human as the punching ball. The yelping sound is one way to make during training. It has nothing to do with play only, it’s the way to communicate. About the actual situation I asked OP how he reacts to this. Yelping isn’t yelling unless it’s a neurotic yelping which in that case it might cause problem. you mentioned science - would you like to explain what knowledge your referring to and what would be your suggestions to solving this situation?