Here's a tip for those with reactive dogs- when counter conditioning a new emotional response to dogs and people, sometimes its better to walk the dog in a new location to train. This could mean driving the dog there, but it is well worth the effort. This way you can start fresh and don't have to work against the areas on your walk that your dog has become sensitized to (like the dog behind the gate on the corner that ALWAYS sends your dog over the top).
Also when in the new area, you don't necc. have to walk far, back and forth will do, also giving the dog permission to sniff and check things out- check out those new smells and other dog smells. Practicing settles in new areas also can help lower arousal.