Bill and Ann on a dogsled trip this week figured out the dog Lewis (shown here). Lewis wanted to pee at the top of every hill.  His top-of-hill leg-lifting meant their dogsled stopped shy of the crest and they had to push it to get it over the top.

Then they got an idea.  As they approached the hilltop, and before Lewis marked the spot, they gave a preemptive command:  "On by. On by, Lewis."

It worked!  Lewis obeyed – or was distracted by the command – and thenceforth pulled their sled smoothly over the hilltops. Kudos to Bill and Ann!!