We recommend starting the off-course obstacle quite a distance away to start (maybe 20 feet). Then, move it closer (about 3 feet at a time) with each successful attempt.
You will notice on the diagram below that we have a tunnel as the off-course potential. However, we include various obstacles into the proofing sessions. You will also want to apply proofing obstacles to other sets so your dog does not become patterned. You want a reliable front cross in all situations on course.
Tip: Remember, a front cross should ALWAYS mean you are turning. Therefore, NEVER front cross on a straight line or you will dilute your front cross cue.