Hello Cyberguy. I'm not sure if this will help, but I thought I'd tell you what worked for my wife and I.
We both did the slow fade thing, but once we decided to stop completely, we had the elders banging on our door on the weekends. We never answered it of course. And they would try to call, but we had caller ID at the time, (got rid of our home phone completely now and just have cells) so we didn't answer the phone. But they started coming by unannounced on weekend mornings (cause it was convenient for them since they have to go peddle books anyway) so I decided to take this approach:
On a Tuesday evening when I knew the PO would be gone, I called his house and left him a message not for anyone to stop by our house at all anymore or to call us. I told him I knew where the kingdom hall was and I knew where he lived.....and if things changed for us, we'd let him know. I did tell him I didn't appreciate him or others coming by here unannounced. I told him that he should respect our wishes and not bother us again.
And that was about 10 months ago, and to this day, we haven't been bothered by him or anyone else from that congregation. We leave them alone, and they leave us alone. I'm not saying this will work in every situation, but for us it's worked great.