Wow what a thread. Ber glad it worked out. As I suspect you know people are actually more competent to defend themselves than they think against a dog. However too many just freeze and try to passivly defend. With training, you have many tools to seriously incapacitate a dog before he/she gets to you. However not many of us have the tools or the practice. A well timed kick, punch or elbow can stop a dog cold, but you need to know what you are doing and have the confidence to stand up to the animal. Most times if you do what you did, i.e stand up to the animal that is enough to stop it.
Have been around long enough to see "viscous" breeds come and go. As Andy said at one time the "bull terrier" was considered one of the best dogs for children - still are in some places. The doberman, and german shepard were breeds that "should be banned" at one time or another because they are inherently viscous.
Have had a number of dogs, all of them in the right circumstances would attack a stranger. This is common to ALL dogs - they are pack animals and are hardwired to defend themselves and the pack. If a threat is percieved they will attack - period. Your job as owner is to be the alpha dog and control "your pack" so they look to you for permission before acting.
Sombody commented re the "herding" instinct of their dog. This same dog was bred to protect the herd as well as keep it together. Not generally a threat, unless a visiting child in some way triggers the "protect my herd" instincts, then tragedy can be the result.
One of my dogs was a terrier - bred at one point to find and kill rats. Came home one day to find the remains of a rat pancaked into the lawn and the dog gleefully pounding on it trying to make it flatter. Peeled it up like a cartoon. The instinct had been triggered and the dog attacked. The dog outweighed the rat by perhaps a pound or two. The point being that as a pet dogs are wonderful, but they all have killer insticts. You can make any dog, any breed, viscous by bringing out this instinct - the larger the dog the more dangerous the result. You can make any dog a danger to others by letting it be the alpha dog of your pack. Then you are putting the attack - no attack decision in its pea brain rather than yours. IMHO both kinds of owners should be liable.
There are no viscous dogs, only viscous owners and irresponsible owners.
As a PS one of my dogs was very dangerous - to men in uniform - when we were not around - and no other person. We had to keep him on leash or locked up whenever he was left alone. Postman, policeman, fireman, courier any male in clothing that looked like a uniform of some kind that came on the property he would attack immediately, unless we were there, then he bacame very agitated but did not attack. Anyone else he was the most gentle friendly animal you could want. This was an english setter cross - known to be goofy and not too bright, but not viscous. Our theory was that he had been abused by someone before we got him - the 8 hours of surgery required to repair a shattered leg when we got him was a clue