Questions, questions, questions
His approach still impresses me, for I've not seen others organize research in quite such a manner. That approach kept us from settling in too quickly on ideas that might later prove limiting, and it helped us discover what we needed to know, not just what we already knew.
Since then, I've continued to discover the power of questions, be it in assessing needs, planning work, or even finding clients. It's not always easy, for there's a temptation to show off one's knowledge through statements rather than possibly showing off one's ignorance through questions (I prefer to regard it as showing off my curiousity and interest), but I've almost always found questions more helpful in the long run. Perhaps you've had similar experiences.