You may remember Talullah from the transport in which Peter and I participated recently. This is her "before" photo in the high-kill shelter before she was rescued:
And these are some "after" photos of her on a potty break during transport:
Notice the difference in her eyes, facial expressions, and body language? Dogs understand more than we give them credit for. Imparting this kind of happiness and relief is addictive. There is no greater feeling in the world.