Notes
First mile was with Rusty and Bruno on leashes. Rusty was being too slow, so I turned around and took Rusty home. I let Bruno run without a leash, and he stayed with me for a mile then made up his own little duathlon in the neighbor's duck pond.
It's official, Rusty; the reason those final miles in a four-mile run are so slow is because of you. :-( Poor old dog.