I'm harsh on this video. IMO it's a dog training companies generic advertisement- buyer beware.
It's hogwash to say a untrained dog will not protect you. Not all will, true. But when someone is in real danger, letting off a scent & a true scared body posture your dog will pick up on that. Again, my or may not react.
This girl has no relationship with the untrained dog, no bond.
Most bad guys don't pop around the corner with a bite suit & sleeve.