Belle and I are continuing to work on the running A-frame, and we're progressing very quickly, as you'll see in the first video. Today, I really pushed it and set up a course around the A-frame. I also tried taking the box off the A-frame to see how well the behavior would hold up.
I decided I really want Belle to hit a few inches lower in the yellow. I added a stride regulator below the apex, hoping to train Belle to land further down the A-frame after cresting the apex. This is really the most critical stride in Rachel Sander's running A-frame method. The dog has to land far enough down and in control of its landing so that both rear feet hit the A-frame and the dog can use them to push off for its bounce into the yellow. If the dog lands too close to the apex, it will be difficult for him to make it to the yellow in one leap. If the dog lands too far down the A-frame, he may leap over the yellow. Also, if the dog doesn't have his body under control as he comes over the A-frame, his rear legs may very well fly up higher than his top line--not a very safe behavior.
I had the brainstorm today to decrease the length of the boxes sides. This gives Belle a smaller target to hit and I can place it further down in the yellow. I also lowered the A-frame back to about 4'8". Belle was hitting close to the top of the box, but she didn't touch it and she was driving further into the yellow. When we practice again, I'll probably try moving the bumper down an inch and see what effect it has on where she lands in the yellow.