Emotive one this
I've had, well i don't know how many dogs, from terriers , labs, pointers, lurchers spaniels, some good some not so.
I got an electric collar about 15years ago and I think if used properly is an excellent tool.
I've seen some horrific treatment of dogs especially from the trialing sector
I've used the collar on training some dogs right from the start, and used it sparingly with some excellent dogs to show at the end, when I say they were excellent , I know they were as I have owned plenty bad ones, most of which would have been down to my inexperience at the time.
I m quite happy to zap myself with the collar, it ain't pleasant but it's not cruel, bu*****d if I'd let anyone hit me with a stick, plenty folk will say "I never hit my dog", look about a beating line???????
I just sold a GWP today, who at 3yrs old was trained with a collar, my vet [a pointer fanatic] has witnessed the full training regime and has never questioned my methods. Her only downfall is that she will now and then run in to a retrieve, if the bird looks like a runner[ie leg down]. Because of this , I decided not to trial her, because I personally wouldn't trial a dog unless I thought the dog could win!
Anyway my point is that anything can be mis used, a lead, a walking stick, too much whistle, your welly boot.
Remember no such thing as a bad dog just a useless human.