I would say that the intent here is to re-inforce in the JWs mind that loyalty to the Df arrangement = listening to Jehovah himself. I see the whole context here as saying that although the Bible does not speak of necessary family business we should not be extreme about it, by creating necessary family business...the person needs to feel a loss over the Df situation, otherwise they won't come back. That's how I see it.
More AGM News-- Spiritual matters continue!
another thought that just came to me- The Wt acknowledged that the term 'necessary family business' is their term, not a Bible term. THAT is what they are saying not to take to the extreme (what they consider extreme) and reason that since it is not in the Bible it does not need to be followed.