Training a dog in schutzhund doesn't make them aggressive. In fact, it trains them when it's appropriate to back off etc. Of course the breeds most natural to it are Malinois, Shepherds, etc. I can't see a Yorkie doing 'seriously' but you never know!
You are so correct! I trained dogs for two police departments while working my way through college. Many dogs "flunked" because they did not have the disposition. And that goes either way - either too aggressive or not aggressive enough.
People always asked me to train their household pets to be "attack dogs" - always seemed hard to explain that we train these dogs to find or "take down" the bad guys but the MAJOR point here is that the dog does not make the decision, the handler does. So training a dog to do a take down or hold is dangerous if the handler is not there to manage the situation that is taking place. Training a dog to do a task that is not going to be supervised by a human is a dangerous thing. The human is the leader and determines what the dog does.
So it is not as slick or romantic as it seems. These trained dogs have to always be supervised and have the special temperament to take the supervision.
Some times the biggest, meanest acting dog is the first one to run under the car when the first shot is fired, while the chihuahua is on the scent trail snarling
