Some interesting articles there, Debra. Of course, most veterinarians are not dog trainers. I was surprised that the vets in the first link supported the use of "gentle leaders", since these are known to cause injury to dogs. They get used because people are unable to train their dogs not to pull. The second link also recommends them. My niece, who is a vet, has seem many neck injuries caused by these tools.
I do use an electronic collar. I use it for a very specific purpose…...to ensure a recall when my dog is loose......and I do not use it for training. Clicker training is faster and a lot more fun! So, I use the e collar for enforcement. Yes, it is an aversive. Funny thing, the way animals learn in nature is by both reward and punishment. They learn what actions bring them pleasure, and what actions bring them pain. The smart ones learn to avoid the pain and go on to live their lives and reproduce. Pain is nature's way of saying "don't do that again!" It is also society's way of saying "don't do that again!" At some point, both humans and animals are going to run up against an aversive.
From observation, I have learned that both horses and dogs are not slow to understand when their own actions cause them discomfort. They tend to avoid things that they find unpleasant, so for example, the sight of a temporary electric fence line dividing the pasture field keeps my horses in the area I would prefer them to graze. Since they know the consequences of touching the fence, they avoid doing that (while grazing within inches of it.) They show no fear of the fence. They know if they do not touch it there are no consequences.
This is the way "invisible" fence works with most (not all) dogs. Properly introduced, it causes no fear, but an understanding that ignoring the warning tone (instead of a visible fence) will result in an unpleasant experience.
The key to effective use of an electronic collar is in the introduction. Done correctly, the animal does not learn to fear it, but to respect it. The "anti shock collar" articles always describe inappropriate usage of the collar, and usually in as dramatic a fashion as possible. Of course, terminology is important here, which is why you will see the term "shock" used. The people on the pro side are also careful with their words, using "stimulation" instead of "shock", but if we can get past semantics what we are describing is a mild and momentary electric shock which can be adjusted over a wide range, from barely noticeable to downright painful.
I've said I don't use the e-collar for training. I have watched training sessions, and they are very low key. What I don't like, either with the e-collar or with conventional collars, is the constant "picking" at the dog. I guess I just don't like "formal" training. Straight sits and correct heeling position are irrelevant on a farm. I just need the dog to do what he's told, and if he stays in a down or sit position, it makes no difference to me, as long as he doesn't move from where I left him. But I do need to be able to interrupt any chasing, and to ensure he comes when I call him, and the e-collar is reliable for this purpose. I use it with my Basenji to keep him safe while allowing him the freedom to run in the fields. He does not fear the collar, although he is "collar wise" (knows the collar is what causes the discomfort, and knows I control the collar). He is happy to have it put on, because that means we are going out the back door to the fields, not out the front door on a leash. And if I tell him "leave it" and he ignores me, I give him a low level stim (shock, if you will), and he gives me a look that says "Oh, if you insist" and stops doing whatever he shouldn't be doing (eating excrement, or rolling in it, that kind of thing). In a normal day, I seldom have to do more than use a verbal reprimand, but if something unexpected occurs.....like the neighbour's cat or a skunk......I have the means to stop the chase. And yes, if he ignores my call I will dial it up and he will yelp and break off his chase and come back to me, and be just as calm and casual as he was before the incident. No more dramatic than if he ran into thistles, which also cause him to yipe. If this is cruelty, I think it is far less damaging than leaving a dog confined in a crate all day long, but that is another topic.
Incidentally, I would never have dreamed of using an e-collar on my Border Collie. But these dogs were bred for cooperative work with humans, and controlling them at a distance is in their genes. Not so much with Basenjis!
Does this look like a fearful, unhappy dog to you?