Dominant dog behavior. The German Shepherd is clearly the initiator, while the Rottweiler is trying to avoid confrontation. The Rott later begins to defend himself, but never initiates confrontation. Notice the GSD hoving his chin above the torso of the Rott. Hovering over another dog is indicative of dominance behavior. It need not escalate further, but it’s always a sign of dominance. In the case of this “fake alpha” GSD, the escalations always occur immediately after the chin-hover dominance maneuver. At one point toward the end, the Rott even anticipates the escalation and quickly re-orients his stance.
Dominance behavior need not always look like this. Dogs at play frequently engage in benign play dominance. This footage is, in contrast, antisocial behavior on the part of the GSD. These aren’t actual dog fights, by the way. It’s called aggressive posturing (by the GSD). The GSD is both dominant and insecure and is attempting to assert his own position in the pack. His lack of self-confidence is reflected in his desire to dominate the Rott in what appears to be an attack. While intimidating, it is not an attack; the GSD is not actually biting down.
Having said all that, I would never allow this sort of repeated dominant-aggressive behavior. Rather than healthy socialization of the GSD, they risk de-socializing the Rottweiler and exacerbating the poor behavior of the GSD. I’m really not sure what the goal was in this exercise, but it’s counterproductive.
Cesar Millan, working with a beautiful but fear-aggressive white German Shepherd. He goes into the insecure Shepherd’s own territory, herds him to a confined space, calmly cajoles a leash around him, and then walks out with him.
Don’t try this at home unless you know what you’re doing. Even Millan wisely grabbed an object to use as a shield if needed. I presume the video was a much-truncated version of real events, as much time must have been spent earning the dog’s trust, allowing the dog to get used to your scent, etc. In the end, Millan’s mastery is impressive.