I don't think that there is any one good action that will work for every situation. When on tour I would never stop and get off the bike every time some dog runs out into the road barking. I would not get very far in a day. I usually speed up if possible when I expect a dog encounter, I would like to pass through the dog's territory before he realizes that I am there. If one appears and chases me then I slow down and talk (sometimes very loudly) to him but continue. The ones that always get my attention are the ones that don't bark but do chase. Especially the really big ones. Had a Great Dane come loping out looking me eye to eye. In the end he was only running to accompany his little friend who barked and acted bad. The big guy was just getting his exercise. There is almost more aggression here on this thread than there is in many real dog encounters.