Similarity between dogs that cause Kasey to “lose it”

I have decided it is not shape, color, or size. I really think that it depends on how the dog is acting. If the dog is controlled, Kasey is eager to meet the dog, but manageable. If the dog is barking out of control and running around or struggling toward Kasey… Kasey loses it. I am clicking and treating him when we walk past yard that have barking dogs… if he: doesn’t bark, doesn’t flail, or doesn’t hop around. Right now I think it is okay if he speeds up a little, looks at the dog, or looks at me, but makes NO SOUND! Do you agree that these are treatable behaviors right now? He seems to do much better if we keep moving, so I don’t stop. If I just have Holly, we stop because I want her to learn to remain calm when others are barking. Kasey is no where near this point.