We are convinced our CHIHUAHUA is the tazmanian devil incarnate! Is this typical of this breed or do you have an "angelic" chihuahua?

A Toe Gnasher is an abomination of nature which is why it gets aggressive with every creature not a Chihuahua. Horrid little things, my mate once killed the neighbours by setting his two Siamese cats on it - the only creature of that height more aggressive

Small breeds are demonic.

With that said, they are trainable, however it requires a bit more care with the human in charge who will tend to adore those little brown eyes and be a bit more protective and "gentle" when it comes to the tiny dog over larger breeds.

Little dogs also tend to be a bit more stubborn, requiring a bit of the "harder hand" or more discipline to break the habits that are easy to form.

We have both a large breed (Black Lab/Rott mix) and a small breed (Snorkey - Miniature Schnauzer and a Yorkshire Terrier mix). the big dog was "easier" to train, the little one appears to have a lot more will and stubborn streak far larger than its size should allow.

Small breeds also tend to be hyper-territorial, this means they will yap even nip more often than larger breeds. Larger breeds tend to growl and let loose with fewer barks - but then when we consider how people react to the bark of a large breed compared to the bark of the small breed (or any territorial intruder) it is clear that the small breed must put on a larger show in order to be as impressive (or scary) as the large breed.

Small breeds are more likely to be allowed to get away with murder, thus you need to make certain you are not helping the dog in this. I would suggest watching the Dog Whisperer to get an idea of how to manage an unruly dog. It is possible to retrain any dog large or small, some require professionals in order to break old "bad" habits.