Great idea for a thread! I have a great success story with a reactive dog aggressive American Bulldog named Jasmine.
Jasmine came to the dog daycare I used to work at. When I started there she had already been attending daycare for a little while. The owners are not particularly dog savvy and had a few incidents with her going after other dogs, but had been able to keep anything from happening. Then one day one of the owners was with the dogs and Jasmine went after a high stress aussie mix that barked constantly. (this dog should not have been in the group to start with because she stressed all the dogs but this is another story) Jasmine got a hold of her and there were a couple scratches in result. Now the owner was afraid of Jasmine and kept her seperated from all the dogs ("time out" as they called it but she never came back from that time out)
Jasmine became full blown reactive at this point, going after dogs and "sharking" them as I called it. Going after them from the sides and smelling them aggressively to the point of lifting them off the ground. Obviously being very rude and pushy, which most dogs would not tolerate and any reaction from another dog would set her into a frenzy.
This was about the time I started there. I ended up talking to the owner about training and her dogs, and she told me that she brought Jasmine there particularly because she had these issues. Well of course that was not a good idea, especially with inexperienced dog people running the place, but she didn't know that. So she hired me to start doing one-on-one lessons and working with Jasmine at the daycare.
I started by introducing her to clicker with the "watch" command away from other dogs. We did sessions at their home and at the dog daycare when no other dogs were present. We also worked on walking with a loose leash, and all the basic commands. We really built the watch command to use around other dogs.
When she came to daycare one day at the start of training, I was not there that day and the owner felt bad that Jasmine was not in the group, and "Ceasar always puts them back in the group" in her words (both owners thought they knew all about dogs because they watched Ceasar Millan on TV, scary I know!)
and a dog that was very reactive and beta, challenged her and he ended up with multiple puncture wounds from Jasmine that resulted in multiple staples, luckily he had a very understanding owner (although I am not sure she should have been).
This set her back to square one. So I started intensely working with her at daycare. First her owner bought a gentle leader for Jasmine. We found this had a strong self controlling effect on her and was very helpful. We never had to put any pressure on the leash she would respond to verbal commands very quickly with the gentle leader. I started with her being in a seperate area and clicking and treating for eye contact and basic commands while other dogs were in view. I would often randomly approach her during the day when she was quiet and calm and click/treat her.
Eventually I started bringing her out next to the pen where the dogs were and practicing her commands. She did excellent. Eventually she could sit next to the fence with other dogs approaching while staying under her threshold.
Next I brought her into an adjoining pen, again with the gentle leader and clicker, practicing commands, and eye contact. My goal was to get her to lay down as much as possible and stay there calmly in all areas.
From there I left her in the pen with the leash on and went into the pen with the other dogs. I would click and treat her from that pen, again giving her commands. She would often lay down and relax and I would give her a "jackpot" for that.
Sometimes the dogs would start playing and getting a little rough and this would start to get her riled up so I would bring her back to a down-stay, until she was calm and then end the session. I always kept her under her threshold and she never charged the fence/barked/or charged a dog.
Lastly, I took her into the large pen with certain dogs I knew were stable and not reactive. She did excellent.
Eventually she was dragging the leash, being calm, and actually interacting with these dogs!
From this point I worked with her owner at their home doing the same thing but in their neighborhood. They wanted to take Jasmine and their other non-aggressive AB on the golf cart for their nightly ride to the beach. But Jasmine was reactive and fight to jump off, especially after bikes, cars, and other dogs. Using the clicker with both Jasmine and Mia, her sister, they could take both for their nightly ride.
They also had a neighbor dog, a older lab, that barked all day long. Jasmine would run straight for her as soon as she got outside charging and jumping on the fence and barking. Again, we used the clicker, using her solid commands to distract her, and even did some clicker with the neighbor dog. Everytime Jasmine returned to us when approaching the fence (before she would bark/charge) we would click and treat. It worked like a charm and I am happy to say Jasmine has not returned to that behavior at all. They treats we used for them were Yummy Chummies, and hot dogs.
This was over approx. a 6 month period.
Sorry so long, but I think this is a great example of how effective the clicker can be. Jasmine was triggered by barking dogs, other dogs playing or running, and other fast moving objects like bikes.