If true, that's not good.
That said, if the dog went after a cyclist, would they not try to paint a defensive kick as an "unprovoked attack"?
Yeah, not buying it.
Whenever a dog bigger than a cat comes at me (not merely just running towards me), I aim straight at the dog, hoping my cargo platform will stop it. It usually means the dog will move andby the time the dog realises my legs was hiding behind the platform, it is too late for it to latch on.
Obviously, if it comes from behind or the side, I try to do things differently. Uphill with the dog behind me can be a real problem.
But really, if you cannot control your dog, I will do whatever it takes to stop it. In that situation, I really don't care that it is the owners who are the real culprits, I'm dealing with their out-of-control dog.
That said, I've found that if the dog doesn't seem out of control, but rather "Play chasing" (can't explain it more than that), the situation is usually diffused if I stop and "chat" to the dog. Not sure that is a good strategy for the next bloke coming past that particular dog, though.