A good friend of mine used to talk about "subversive" people--people who didn't want you to do well because it was a threat to their perceptions of themselves and their own abilities. I think it's a mistake to start right off by underestimating people. In my experience, most of the people I deal with are smarter than I want to give them credit for initially. An amazing number of them are pretty capable of learning on their own. Putting them down doesn't do a thing to help them.