What about if you could get people he meets to do obedience with him? Obviously, this would be on a case by case basis...
What if you say "He is afraid. If you want to meet him you need to listen to me" or something?
Maybe you could teach a rock solid Sit for these situations so you can have him Sit and then step in front of him?
I wish I was closer I'm getting really good at working with Shy dogs - can bring them out of their shell usually within a few minutes. I would bw able come over and help, and then we could go walking and I'd back you up and block the crazies
Oddly around here I find kids to be the best listeners. They always ask and they LISTEN to the response, too I had my SIL's dog and Oscar out a while back, Bram is super skittish, doesn't really like to be petted and definitely not by new unusual people-nevermind children. I had 2 kids come up to us and ask if they could pet the dogs, I put both in a sit and replied that "this one" - Oscar, was friendly, but "this one" was not- Bram. They proceeded to pretty well maul Oscar, who loves this stuff, and ask about him, and didn't so much as blink at Bram (my SIL's dog). I find that young kids almost always listen Too bad adults don't.