Anne, I didn't mean to imply that politeness would necessarily work for you (though I am wondering if "Whoop-di-doo" counts as politeness in your understanding of the term).

I can only say that it worked very well for me, and that I can see reasons why it should work, and that I think it would probably work for most people, at least better than some of the emotional responses given here.

Your case sounds very unusual. I myself had a very unusual experience, maybe even stranger than yours, but it was a case of in-person soliciting. A young man would knock on my door each day and ask for a job, though I ran no business and was a low-paid employee barely able to make my rent and so certainly not in need of servants and not someone who could help him find a job. He would show me business cards, which he thought proved he had worked for and was recommended by the people on the cards. And even when I gave up trying to convince him, and ended the conversation and closed the door, he would sit on my porch and wait, sometimes for hours. He was small and thin and didn't appear to be a threat. His manner didn't suggest psychological problems or retardation; he just seemed like a young man desperately looking for a job. But it was a nuisance. I had to at least open the door, since it could have been a friend dropping by. I still have no idea why it happened. Maybe he knocked on a lot of other doors too, and I was the only person who didn't threaten to shoot him or call the police. So in this case politeness may have worked against me.