I personally don't recommend pure positive, I do feel that dogs need corrections when earned, but I don't train yank and crank either. I use food to initially lure/shape, quickly move to random rewards with food or toys (depending on the activity being taught and the drive levels the dog is working in).
For most of my dogs, a correction is often as simple as a voice correction "ut oh!" when we're training. If the dog is in drive and being an a$$ about something (i.e. not controlling itself while another dog is running agility and being a nuisance), I have no qualms about a solid collar correction or a "3 foot sit" (dog is picked up by fur near neck/jaw line and moved 3 feet backwards into the sit they were supposed to be maintaining
)
I do a lot of training out in Auburn MA (near Worcester), literally right off the Pike. The instructor is someone who teaches using clicker and positive, but also isn't averse to giving a deserved correction (though I've almost never seen her do it in class.....I just know she does use them on her own dogs).
http://www.collinswoodk9.com
Out of curiousity, was you instructor's name L? I wasn't sure if she was still in dogs or not........I remember taking Bort there 9yrs ago and watching similar antics and thinking "this is NOT how I want to train." I did belong to a USRC SchH club there for a few years before seeking out another one.
Anyway, good luck! If I can be of further help, feel free to email me or PM when you get the capability.
O, and if you're interested in agility, there's a trial in Wrentham at the State school on 4/30-5/1, the Grrrrlz and I will be running (I'll be the obviously 8.5mos pregnant woman).
