I was reading something about a cyclic theory of disease and it got me thinking about the JW mindset, and how we try to change it. Sorry for the long winded message, I just got up and I'm not as lucid as can be. I think you'll get the basic gist of what I'm trying to say though..
Often times we seem to think in terms of a single cause, like the witnesses calling on you in the beginning, your parents and when they were first called on or whatever. But the fact is, you needed to maintain the attendance of 5 meetings a week, go to the assemblies and conventions, go out in field service and associate with other JWs and so on. If someone just got called on once, chances are pretty slim that they became a witness. In other words, you had to keep going back to witness teachings for it to stick. (compare that with simple truths that you only hear once to remember, that should tell you something)
In terms of how this works in a circular pattern, it obviously feeds on itself. Of course, the pattern itself is not a problem, so long as it's open to the larger environment known as the reality of life. The problem is basically the isolation - shunning of 'worldly people', former members, people who might be pegged as 'bad associaton' and so on. Basically, you might say it's a simple question of being open.
Now compare this with the approach of using some specific line of reasoning to question their belief system. That is essentially trying to unblock specific beliefs to create small openings, but the overall picture is their mind being closed and even keeping a closed door on a social level, and I would say even between different compartments of their mind. If a person was only exposed to the WT teachings and then went about their business of living life, it's probably pretty unlikely for them to become a witness. Even if they continue to hear about it, all things being equal it doesn't have any more of a chance of taking hold than other things.
This is where disease susceptibility comes in. Although we tend to think of an infectious organism as the sole cause of sickness, the fact is the person's immune system has to be susceptible to the pathogen. In this case, the susceptibility to the witness thinking might be some kind of emotional vulnerability. So one way to look at it is you can approach it from both angles of breaking down the pathogen and strengthening the hosts immune system, but this really just comes down to a matter of viewing it as one system. In fact, it's just the big system of life isn't it, you and the witnesses are only parts of it.
So I think just helping them relax is a big part of it, because people are naturally open to the world around them or just to their own mind, after all there's probably already plenty of thoughts that contradict each other in there. There is an intuitive sense that this is healthy, so I think they can learn that this is good just by virtue of the fact that it is less stressful. People also become less defensive if you don't say anything in a challenging manner, so it's really helping them relax by approaching it in a relaxed manner yourself. If you react, they'll probably react.
There are times, of course when it may be appropriate to be more forceful because there's no time to lose, but generally speaking I would think it's kind of hard to make that call. Certainly if it's a life or death situation like the blood issue that will be a reason to take the specific, targeted approach, but it would be important for us to ask whether it's our desire to get them out or if it's their need. Of course it would be better for them to be completely healthy regardless of how serious it is, but dealing with a witness is rather like dealing with a child who doesn't want to take the medicine. Other than medicine, though, there are actually a lot of things we can do to promote good health.