I think that if you feel you have no choice but to knock on doors... why not add a little extra something to your message? I think creativity is called for.
To the householder who answers, say, "Hello, I'm a Jehovah's Witness and I have decided it is best to be blunt. I want to warn you that if you don't join our church, you will die in Armageddon with 99.9 percent of humanity."
Add a written freeminds.org (or even a label) to tracts that you leave.
Figure out something at least a little daring and a good excuse if you are caught. They'll really wish you wouldn't be in FS if you do this right. Then, of course, come back here and let us know what you did.
bebu