Wasp spray does not cause immediate blindness or any long term damage. I used it about 4 years ago on a neighbors dog. The dog will only come to the edge of the road and not out of its yard, still. Its definitely not the most popular solution but it does work. I would only use it for problem dogs on a regular route. Most of the time I just ride straight at them and they turn and run. By the time they give chase again you are going fast enough to be out of danger.

I have had a couple of friends bit with serious injuries. I don't care if it is a bad owner it is still the dog biting. If the owner doesn't take responsibility, then its up to you to train it. I don't like the idea of giving them treats that only lures them to the street. Do whatever you need to and let them know their yard is the limit of their territory.