All of the above. Spray HALT, spray a water bottle, out-sprint the dog (if you think you can), stop and put the bike between you and the dog if you can't, YELL at the dog (NO! GO HOME!), just be ready with all those responses, and use the appropriate tool for the situation.
One other thing is avoidance- if you see the dog first, and can avoid it, do that. I do a lot of urban riding, and when I see a dog, a lot of the time I can jog over a block and avoid it- that sort of thing. Your fear of dogs is good for that- use it to drive your "dog radar" and try to see the dogs before they see you.
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I stop for people / whose right of way I honor / but not for no one.
Originally Posted by
bragi 
"However, it's never a good idea to overgeneralize."