My home state has a reputation among touring cyclists.......Many who travel the entire Transamerica Trail remember this state as having way too many dogs out on the roads chasing after the cyclists. That's not flattering but I must admit that I'm used to it. Being a good bike handler gives me enough confidence to battle off the dogs on a daily basis
Because of my youth revolving around bicycles, it just never occurred to me that a person who is less than 100% confident in their handling abilities might be scared of a charging dog. My wife became a pretty serious bicycle commuter well into her adult life and never built up the skills of a freestyle riding, dirt jumping, downhill mtb racing youth. She's confident with dogs of any sort when she's on foot but she's MUCH less confident if they pursue her while she's on two wheels. Where I might kick both legs towards the dogs while simultaneously squirting them with a water bottle, she worries more about simply staying upright. She's a very competent rider but this variable of a dog that can hit her front wheel or otherwise knock her off balance is just a little too much of a worry. She has helped change my own attitude towards charging dogs.
Back in the old days, I would ride along and ignore a charging dog. Never got bit but I did get rammed a few times and even accidentally ran over one dog but it was okay. Now that I'm more aware of how uncomfortable a dog can make a cyclist, I've changed my methods. Now I actively train people's dogs for them. One thing to use is "Halt!" dog repellent and it works well. It actually does train the dogs if you regularly ride that area. Another thing I've used is a frame pump. These things aren't that tough but I have used them for a swift whack on the snout. Another method I've used is direct conflict with the owner and this could easily lead to fisticuffs so I don't suggest it. Honestly, any of these methods can lead to a fight with a protective owner so it's all done at your own risk. Weigh the pros and cons to see if it's worth it to you.
I'm training all the local dogs for the sake of my wife being able to ride with confidence and others will probably benefit too. There is no good reason for a dog to pursue/attack anyone on a public roadway so it's a no-brainer for me to help them stay in their yards.
In this photo you can barely see a busted Zefal frame pump poking out of the Carradice bag because it had a meeting with a dog snout.