i just had surgery on both knees. Still trying to do some training. Dog sees the crutches I'm running on and thinks I have a secret weapon to make her sit. The sit drill I was using before surgery seemed to have an effect, however I won't really know till I get her to the next test. until then its gonna be drill drill drill. a couple of yellow bats in the field .....what a great idea.......when she broke at the last test, she came right back when I called her, she only got about 10 feet in a second. i used the 2 collar thing at a training day, however missed the one this week end because of my knees.