You are welcome to your opinion, I use e-collars to teach my dogs not to jump up on people. They don't think the person is attacking them, they just learn to sit and wait to be petted. The woman was asking for advice to save her dog. I gave her an option to try before resorting to more drastic measures. I'm fine with her killing her dog. We have enough of them in this world and a lack of dog Savvy peopleit sounded like a high energy timid dog. Not aggressive. The part where the "18 month old" child held the ball and the dog scratched her face. Was that aggression or over excitement? I feel as though these people were not capable of owning such a doc and a more experienced dog person could do better. But that's just my horrible advice. Yours was much better.
An experienced person can do that, yes. An inexperienced person has a much higher risk of escalating the problem from simple fear into outright aggression.
Also, a fearful dog needs to be handled differently than one who is simply over-excited and/or forgets their manners.
I agree that the dog is most likely not aggressive in the true sense of the word. He sounds incredibly fearful which may be due to his past experiences or may be that he is genetically unsound. Unfortunately, a fearful dog is much more dangerous. An aggressive dog, you know what you have. The dog is in your face and will let you know when you step over his line in 99% of cases. Fearful dogs have different triggers and problems. You often can't tell (unless you are an experienced handler) that the dog is being pushed over his limit.
Our rescue Freya had this problem. She was never brave enough to growl or to act out aggressively towards people. She would wait until your back was turned and then rush you with a show of teeth and noise and hope to scare you away. Do I doubt that she would have bitten if she felt there was no chance of escape, absolutely. Unfortunately, she was so afraid of strangers that "no escape" could be as simple as someone standing in the only door into the room. Thankfully the OP's dog (or most dogs) aren't that bad.
IF the OP wants to try to keep the dog, absolutely an experienced trainer/behaviorist. Not someone who teaches training classes but who has experience in dealing with reactive/aggressive/problem dogs. IF the OP can regain her trust that the dog won't be a danger, then keep him absolultely no doubt. But, trust is a tricky thing. No, I would never keep a dog that I didn't trust and I wouldn't recommend that anyone else do it. Lack of trust and fear of a dog can often be a self-fulfilling prophecy. Mom is nervous whenever the dog comes near the child. Dog doesn't know why, but thinks "oh this little person makes mom scared. I'd better keep an eye on him he might be dangerous." Dog's escalated behavior makes mom MORE upset. Dog, being a dog, thinks that the problem is the scary child and becomes even more reactive. Just not a risk I would take.
Now, if the OP is dedicated and has the facilities to 100% keep the child and dog separated while meeting the needs of both, that would be a win-win situation. Dog gets his attention and exercise and all his needs met every day. Child is kept far away and has no access to the dog at all. This also works nicely because even dogs that don't do well with smaller/younger children have no problem interacting with an older kid. (Dogs find kids to be strange animals. They look like humans but smell, act, and sound different. They make high pitched noises and move quickly and randomly.)