I cycled from Manc to Lonon in July. I encountered many dogs and only had an issue with one, fortunately, I was traveling relatively slowly at the time. Everyone, no matter how they are traveling needs to respect other users, it also helps to be gracious to the idiots that we all encounter. I was very greatful to a boater who made me a brew at Fradley Junction after a particularly tough day and many others I met along the way.
Speaking as a biker who has a few selfish people riding off roaders round my estate dispite the potential dangers to young children etc. I think motorbiks need to be kept well away from the towpath.