+1 ... good comments!

Looking at it from a dog owners perspective, if my dog
were somehow causing that kind of threat/problem, I would
WANT someone to pepper spray it. It may save it's life
in the long run and certainly will make for more friendly
neighbors if it isn't a threat or nuisance.

I don't think anyone expects the police to show up fast enough to protect from an imminent dog attack. The point is to report the owner to the police and hopefully that will prevent such a situation in the future.

It does matter where you live. I've never been hiking on public land anywhere in the country -- local, state or national -- where dogs were not required to be on leash. Whether the requirement is enforced is another matter. In any event, people are criminally and civilly liable for their dogs attacking people.

And in my experience, private landowners have been even more strict about leashes because they've had livestock.

I have gotten pepper spray on my face because of a leaky container.

That tiny amount of exposure was very unpleasant, and immediately so.

If you hit a mucuous membrane, they'll stop.

I work primarily outdoors, and carry pepperspray as part of my work kit. I have had good results with pepperspray that is ejected in a stream or spray. Foggers, for me, have been useless, because of their susceptibility to breezes. Make sure you hit the eyes, nose, and mouth.

I used pepperspray as a first defense on all dogs, until the day I was caught offguard and offduty, and was chewed up. Since that attack, the pepperspray only comes out for dogs that I think I can punt. Large dogs have gotten lead when their owners were not there to control them.
If you wait until the dog bites, you will not get a clean shot.

A dogs reaction to pepper spray depends on the specific dog and motivation.

As for Blast's rottwieler encounter, I wasn't there to see the dogs posture, but two rotties would not be stopped by a stick if they were motivated. IMO they were posturing and being very defensive for their person. While these rotties were very protective and may in fact be good dogs, the owner doesn't have anything close to an adequate level of control. Any dog in the rottweiler class that is walked off leash needs to be fully and reliably trained. The fact that she needed to physically pull them away tells me those dogs have no business being off leash in public. They probably need to be socialized with people other than their owner and the owner needs to learn how to control them.

That said, years back I encountered a couple German Shepherds in my back yard. These two dogs had done the barking snarling thing to a female neighbor and while I like GSD's, these two were potentially dangerous. I called LE, explained the situation and the dog's rep, and asked them if they wanted to handle it or would they like me to shoot them ("No, don't shoot them"). Animal control took care of it.

Notes about calling the police:

1. This particular area is right on the border between two counties. Last year I found a stolen vehicle ditched there and had to call SIX different LEO departments before finding one who would respond. The really amazing thing was the stolen vehicle belonged to a cop and his uniform and paperwork were strewn around.

2. I was just starting the class and didn't want to interrupt it to deal with police. I don't charge for the class, I just accept tips afterwards. Plus, some people had driven over an hour to be there. I didn't want any of them to feel the class wasn't worthwhile (ie. cut into my tips or make them not tell their friends about the class). I'll admit that's a bad motivation, especially if these dogs do hurt someone else in the future.

3. The owner of the dogs was gone well before we returned to the parking area so getting her license plate number wasn't an option without interupting the class.

4. There are signs stating dogs must be kept on leashes.

Thinking about it I should have told one of the students to film the encounter. Best case it would have proved the shootings were justified, worst case it would have made an awesome youtube video...

I don't think the dogs were just playing but they weren't in full-on attack mode, either. They scared the heck out of one of the students who stood there screaming in fear. Like someone else said, my stick wouldn't have done anything against two Rotts bent on eating me.

You always read about time slowing down in such an event and that is completely true. I remember running through all sorts of analysis and possible actions during the brief encounter. One of the main reasons I got a CCW was due to previous encounters with dogs and I've visualized armed responses to such an incident over and over in my mind. I think that helped prepare me for the real thing and kept me from freezing up.

-Blast, who is getting too old for this sort of excitement.

Good Call all the way around, Blast!!!

Sage advice. That's why I carry pepper spray 100% of the time, in the city. And bear spray in the woods, always.

And if attacked, I'll call the police, park rangers or whoever the authority is.

I was once attacked on the street by a two-legged perp.

There is indeed a different time perspective. Perhaps because you are so in the moment.