I'm going to throw in a bit too....
A lot of my dog's stay work is done on a flexi leash and prong. Flexi leash is flexed out to the maximum distance, and rests on the floor. My foot rests on top of the flexi. Any air scenting, checking out the other dogs, shifting of position which may lead to a down on the long sit, or a sit on the down is corrected while I am at the end of the flexi with my foot. Cam was taught a tension stay meaning that if I pull backwards he braces backwards in effort to hold position.
My instructor who I think very highly of and who has taught some of the top OTCH dogs in the country, along with having one of the top BC's herself has the motto that if you have to go in and correct your dog once for a broken stay, or ill behavior, it is a mistake. If the dog does it again, the dog does not fully comprehend the exercise, thus belongs out of the lineup to practice it on his own. There is so much stress in the lineup that constantly going fowards and backwards to correct, reinforce the dog is unfair to the other dogs as it is a stressor to them as well.
I know if your dog was grumbling in a line up where I train she would have excused your dog, and asked him to practice in an area where he wasn't disruptive to the other dogs..... I know she wouldn't have made you leave the training facility, but there is no place in the lineup for that type of behavior, playing or not.
Keep your chin up though. I switched trainers last year from a corgi person to a BC person that also had great success with bloodhounds. She loves the drive of my dog, loves his pushiness and embraces his attitude. She pushes me to drive harder, just as she has me him drive harder.... Because I have the comittment to succeed and achieve greatness, and because I listen to her words and practice hard, she puts the time and effort into myself and my dog that we need to suceed.......time to look for someone who can do this for yourself.......
