For me this periodic requirement to start from scratch and quickly learn the intricacies of a new field is one of the chief joys of consultancy work. I enjoy the sense that I've gone from zero knowledge about an area to maybe 85% comprehension in a matter of days.
I think that much of this pleasure comes from what Zen philosophy calls 'the beginners' mind': -
Having an attitude of openness, eagerness, and lack of preconceptions when studying a subjectI trust in my ability to quickly learn enough to ask intelligent if somewhat naive questions. In fact it's the quality of these questions that dictate my worth as a consultant.
Being paid to be a constant beginner can be liberating but of course it comes with a caveat: 85% comprehension is a very long way from mastery; tomorrow I need to know just enough to help my clients see their world through fresh eyes.