I recently saw a man coasting on his bike as 3 sled dogs happily pulled him along. He was getting a free ride, doing no work, and the dogs loved it.
Now, I don't have a sled dog nor do I want to be pulled - I love the exercise. But I would love to have a companion on my rides. My wife won't ride with me, so I'm hoping someone has experience with training dogs to stay close. Running without a leash is not an option.