I don't have the letter to BOEs, but Blues Brother's description pretty well matches what we did.
We would make sure to have a "quarterly meeting" early in the calendar year in preparation for the "Memorial Season" (tm). The PO would rattle off at least a couple names of DFed ones known to be living in the area who he thought were "worthy" of a visit. Here's a few things that would make you "unworthy".
1. Still living in sin. (Playing the Lotto, Smoking once a month, etc.)
2. Blowing your stack the last time you had contact with the elders. This would generally get you at least a 3-4 year reprieve, and a permanent one if you threatened violence.
3. Having Apostate views. (Scum of the earth not even worth mentioning.)
During my last year serving as an elder and 100% awakened to the cultish nature of JWism, I was assigned to call on a nice young man who was deemed to be a good possibility for reinstatement. He was DFed for doing what comes natural with the woman he loved, but had since married her and had a child. I wrestled a bit with whether or not to be the one to call him, but in the end I figured I was actually the best elder for the job. My plan was to be very kind, but to make sure not to heap ANY sort of guilt or judgement on him whatsoever. It was more like "Hey, are you happy with your current car insurance company? Yes? Oh, OK, just checking. How's the job at ________ working out?...."
When all was said and done I'm fairly certain he realized I was just doing a routine job for JW elders, and that I was genuinely happy that he was living a good, productive life free of the JWs.
He's still long gone. Good for him.
om