I only used the arguments that I have posted on this forum previously, it was just in real life. It worked exactly as beautifully as I thought it would. The elder has never been taught a response for those points because the Reasoning book doesn't HAVE those points. The Watchtower Society has never commented on those points. And they can't respond on their own, can they? Not without permission from "mother", right?
What I didn't do was address the things he was ready for.
This is what I've been saying all along. (To myself anyways. :) ) Talk to the JWs about the trinity, hellfire, ransom, end times, etc... and they have answers they can parrot. More than that, they have the fervor of conviction because it has been hammered into their brains over and over and over...
Instead, by addressing something they don't really cover in publications or the "Reasoning" book, they have to access their own reasoning ability to try to reply, instead of just accessing rote and memory. Fantastic. We had my dad over for dinner tonight. I tried to do something similar... just slipping around the edges of reason. Not nearly so effective as what you were doing, but interesting still.