Susan Garret's videos mention Circle Work, also called Flat Work and Shadow Handling, so I thought I'd look it up on the internet. This teaches D how to follow H's cues between the obstacles. I found one article on the internet, by Terry Long, which I copy here because the link has since gone down. Enjoy!
"Your dog may have mastered agility obstacles, but how well does he handle the flatwork in between?
If you were asked how much time you spent teaching your dog the weave poles, you probably would be able to come up with a number framed in hours, weeks, and months. When asked a similar question about the teeter-totter, you might come up with a pretty realistic number for that, too.
If, however, you were asked how much time you spent teaching your dog how to run in between the obstacles, you just might be stumped. That’s because many agility handlers focus almost exclusively on training the obstacles. Yet, it’s “on the flat” that most problems such as off courses, knocked bars, and wide, loopy turns occur. And frequently, it is a dog’s misunderstanding of our body language, as well as our poorly timed turning signals, that cause these problems.
Foundation training that focuses on a dog’s understanding of our body language is called “flat work,” “shadow handling,” or “circle work.” It requires nothing more than the handler, the dog, and some rewards. Not only is no equipment required, it is important to practice your circle work without equipment nearby. You do not want your dog to inadvertently take an obstacle when you do not cue him to do so with specific positional cues. But that’s for another lesson entirely.
Why do it? Circle work has many benefits. Your dog will learn to:
• Enjoy running with you and responding to your physical cues.
• Run along both your left and right sides, not forging ahead or drifting wide.
• Turn tightly to your body (and later, around a jump stanchion).
• Interpret body language such as acceleration and deceleration.
• Keep driving straight forward unless you give specific physical signals such as shoulder turns (to redirect the dog after an obstacle) and arm changes (front crosses and threadles/pull-throughs).
• Not cut in front of you.
• Not cross behind you (blind crossing).
• Not practice herding behaviors such as flanking (moving laterally away from you), nipping, barking, or spinning.
Getting started: We’ll begin with teaching your dogs to run the “outside circle.”
1. Choose a reward your dog finds very motivating. This can be a tug toy or treats.
2. Start with your dog on your left (you will repeat these exercises on your right later). Move in a clockwise direction. Ask your dog to hand target your left hand (this assumes you have taught this foundation skill previously) by stepping back with your left leg and placing your left hand, palm outward next to your leg, for your dog to touch. When your dog touches your hand, say “Yes,” and step forward one or two steps, rewarding your dog when he catches up with you. From this point forward, you will “pump run” keeping both your arms up and your hands in fists.
3. Be sure to reward your dog close to the side he’s on. Do not allow your dog to cross in front of you to grab a toy from your opposite hand. If you do, you will be teaching your dog that it is okay to cut in front of you.
4. Start moving in a very small circle (not much more than a step or two), generously rewarding your dog for staying at your side.
5. Keep your sessions short. Use 10 treats on the left (or 10 brief tugging sessions), release your dog, and take a break for a couple of minutes.
6. Repeat 2–5, starting on the right this time, moving in a counter-clockwise direction.
7. Gradually increase the size of your circle and the number of steps you take between each reward.
8. Increase your pace so that you are eventually trotting or running a large circle.
9. Accelerate hard and reward your dog for accelerating and catching up with you.
10. Decelerate, and reward your dog for checking his stride and staying next to you instead of driving past you. If he does pass you, withhold the reward and start over.
11. Decelerate and stop, and reward your dog for not driving past where you stopped.
12. Be sure to practice 7–11 on both the left and right sides, moving clockwise and counter-clockwise, respectively.
13. Once your dog masters the basics, teach him the front cross. Start with your dog on the left and run a straight line, but practice the following footwork and before trying it with your dog. To execute the front cross with your dog on your left, hold your reward in your right hand. Then, with your invisible dog on your left, pull back your left shoulder and turn your right shoulder in toward your dog, pivoting in toward him. Bring your right arm across your body as you turn toward him (this is the beginning of teaching your dog to respond to an arm change). Drive out of the turn by taking a step in the new direction. Reward your dog when he catches up to you on your right. If your dog tries to cross behind you, pivot to your right, back toward your dog, interrupt him, and start over. Now try it with your real dog! And don’t forget to practice both sides.
To teach “inside circles,” start with your dog on a leash so you can better control his position. Repeat all of the above steps with your dog on the left and running counter-clockwise and then on the right running clockwise. Inside circle work is more difficult, so remember to raise your rate of reinforcement and use your leash until your dog understands the game.
Terry Long, CPDT, is a writer, behavior specialist, and agility instructor in Long Beach, Calif. She can be reached at email@example.com.