[Heacechig]

I had this same exact situation in my neighborhood. I didn't approach the guy, but eventually he saw me out working the dogs and walked up on his own. After the normal howdy do's, he mentioned that he was going to breed his dog. My reply was "Why?" Of course it was because of all that money he was going to make. So, in my nicest, friendliest personna I proceeded to tell him all about how much it was going to cost him if she had complications, and every little negative thing I could come up with to scare the P'jesus out of him. Even to the point of telling him that if one of his puppy owners had a problem, he would be responsible for taking the puppy back. (I did my best to make it sound like this legally enforcable - although we all know it isn't.) But whatever...
It worked. Ran into him about 6 months later and he told me he had gotten his dog spayed. After that he came over for private lessons and the rest is history.

The best thing I have found for education with these people is to have my dogs well under control and let them see how these dogs should be. When they ask about it, I'm off and running. If they want well behaved dogs it works great. If not, they go on about their business and do what they do. Of course all the other neighbors continue to give them sh-t about not getting their dog under controll when most of the rest of the big dogs in the neighborhood are awesome. This in itself works wonders.