James,
Schutzhund is, indeed, protection training and it incorporates a lot of basic obedience training in addition to the bite work. Most of the dogs that do Schutzhund are German Shepherds, Rotties, Malinois and dogs that you would normally associate with police work.

The key to Schutzhund is the release: all dogs can bite but a well-trained Schutzhund dog will always release on command. If properly trained, it is a sport and the dogs actually enjoy the "play" with the agitator and the sleeve is thought of as a "toy".

Although I own Rotties, I don't work in Schutzhund. I do, however, respect the dogs and people that do it well and I've shot a bunch of Schutzhund trials. In my household, my Golden, Crash, is the only dog with the temperament to actually get a Schutzhund title. Dee Dee, can you imagine a Schutzhund III Golden?

Jim