I agree that a UOF continuum is necessary. I've learned this the hard way from being menaced and attacked a few times. It literally sucks having only your pistol to deploy on a charging and aggressive dog. You may miss, it is loud, and I'm basically gonna ruin my day and have to deal with the local PD for the next several hours. No thanks. I'd rather get the baton and strike the dog hard. If the situation becomes worse then I go to a pistol. In no way am I ever going to go hands-on with an aggressive dog.
Here is my take on this...
There are a multitude of reasons why the UOF bar is lowered with a dog.
First is that it is an animal that possesses limited critical thinking and reasoning skills. Once it has decided to attack, you have zero options to figure out its intent.
Second, In reference to the human biting analogy, a large breed dog bite is a serious injury about the magnitude of a knife wound. A dog's bite and teeth are a weapon endowed to them by nature. They know how to use it very, very well.
Third. Dogs pain tolerance and 'drive' goes sky high when they experience an adrenaline dump. going hands-on or kicking should be your last option, not first. You need to decisively ensure that you are going prevail. The dog is going to fight to the death or is willing to take things to a limit most humans aren't prepared to go. In other words, it isn't a big deal for a dog's flesh to get ripped up, for a human it is very painful and very expensive.
Fourth. Dynamics. Dogs are quick, agile, and have probably 3+ times the cardio endurance a human does. A chain saw with fur.
These are the reasons I lower the UOF bar on dogs. And the bar is progressively lowered the larger the dog.
I have a dog. It is babied. It is part of my family. I like dogs in general. This doesn't mean I can't recognize the threat a dog can bring. I also know that despite my dog being very docile, she possesses the ability to lash out and attack. I wouldn't blame someone for defending themselves as they see fit.
I don't second guess a cop or civilian's decision to use lethal force quicker on a dog than they would otherwise on a human.
Edit: About OC and MACE. I've ruled this out. Dogs are too quick. And at night it is impossible to aim. And where I live the wind blows strong enough to push it back into your face.
For me it is #1. S-A-W. find the dog beforehand. Call the PD and complain. #2. If you can't do #1, get the baton. #3. If #2 doesn't work, then go to pistol.