I <3 Malcolm Gladwell (if you're not familiar with this fragment of geekiness, tip your head to the right).
I still haven't read The Tipping Point, but blink has been very helpful to me to explain to clients why it is useless for me--or my clients--to script client interactions with a parenting evaluator or otherwise try to influence the evaluator's thinking.
The source of my clients' unease, and consequent desire to control the evaluation process, is obvious. In a parenting case, everyone needs to think of the evaluator as God. Yet the evaluator is an aloof expert, urged on the client by an attorney--any attorney--whose expertise that client also finds impossible to evaluate.
I have read--but can't find a cite to the original research--that when we communicate face-to-face, the majority of communication is visual, through facial expressions, the next most important is information that is heard other than the content of speech, and least important of all is the actual content of our speech. As a professional wordsmith, I find these statistics disappointing, but I can live with them. Based on my personal observations, I also think they are correct. However, I can't convince clients of that. But with Gladwell's book I can point to research (even if anecdotally related) for that same proposition.
Of course, this only demonstrates that a good evaluator can cut to the heart of things, not necessarily that the evaluator in any particular case will cut to the heart of things. Faith in an evaluator can be misplaced. But that's another rant for a different day.