My research said that it can work if you do it right. It is very hard and requires constant monitoring of the dog. I wouldn't recommend it but it will work better than cats. The problem I can forsee is a vegan owner moving there dog to a vegan diet and then refusing to accept that that there dog is having health issues because of it. They would need to be willing to start giving there dog regular food again but I don't see the extreme vegans doing that. They will likely just shove there head in the sand or blame something else like the vet.

Yeah, it's ridiculous to feed a dog vegetables. My dog gets a diet of pure meat. I drive around my city with a net gun and capture outdoor cats, and then butcher them for Fido. It's a win-win-win. Win: Fido gets meat. Win: I don't contribute to factory farming cruelty. Win: the native birds aren't driven extinct by predation. This is the only ethical way to feed a dog, since this way every living creature that ends up in Fido's hungry jaws lived a rich and fulfilling life.