Your dog's position on the teeter may be contributing to avoidance behaviors, lack of efficiency or broken stopped contact criteria! Flash demonstrates two teeter positions in this video, straight legs as the board hits and a bow position as the board hits. You can see for yourself which position is more stable!
If you're looking for more resources on training the teeter or other agility skills, check out our Training Library on Agilityandbeyond.com
Link: http://www.agilityandbeyond.com/training-library/