Staying within a Pattern for Reactive dogs

When an on-leash reactive dog is barking/lunging/pulling to another dog on-leash, it doesn't make going for a walk or being outside enjoyable. Anyone with anxiety is told to control your breathing and have a focal point to concentrate on, so your mind doesn't start to go overboard. When you put a dog in a simple pattern like in this video of going side-to-side which he is running back and forth from A to B it makes the trigger from a distance not the focal point. The dog has learned how to stay within this pattern and not react to the trigger. https://www.youtube.com/watch?v=en1dYvY61cU