The advantage of one dog, easy to focus more on the training. All I have to do is walk the opposite direction, say ABOUT or LET'S GO. Of course it helps if the dog can hear you. Getting in front of a dog to give sign language can be difficult.
All is an exaggeration, I should say most of the time. We also have an emergency call I really should practice. He knows a quick response will provide a ton of treats.