I actually can partially agree about the shock collars.
I have trained, or been lucky in the training of 6 dogs, failed miserably with one, and have not used on the puppy.
I use it as an extension of my arm, which may be wrong. I don't leave the collar on so the dogs know what they mean, again wrong.
I only use it high enough to get their attention. Right- meaning this is correct, not sarcasm.
When they give too much attention to a subject, a quick no, or my chicken.... if that doesn't get their attention zap.
I usually retrain every once in a while when they get too froggy with ignoring the come command, and use it extensively in the field with my beagles, but usually stay away from it as a general rule.
The one I screwed up with, I think there is something wrong with that dog. My girlfriend rescued her 5 years ago as a puppy. She had always lived in the backyard in the city, a yard fenced by a wooden privacy fence. We found out that she had been getting out by neighbors and assumed she was getting out of the gate. I took her to the farm and put her in a fence made of cattle panel. She is Boxer/Great Pyrenees mix and climbed it. Next I put electric at the top and bottom. She hit the electric, backed up then cleared it. I used the collar, she felt the jolt.... well it took a while (hours) for her to come back home. Well I put her in a 10x10x6 kennel fence.... climbed it. Then I put a roof on it.... chewed and pulled the chain link apart. Next, took her back to town. Got a call from the warden that he witnessed her go through, yes rammed her chest through the wooden privacy fence and jumped on an old lady (thankfully a friends mother), not in anger but in greeting I suppose.... Now, she stays inside.
Anyhow, I do not hold myself out as a dog trainer, only share my experiences so that others may or may not point out what I may or may not have done right or wrong. Bottom line, I don't have the ordinary predator problems of coyotes, coon, possum, etc which I attribute to the dogs, or their smell.