— Where does the referenced person shine? What kinds of work did the referenced prefer to do?
— What kinds of people does the referenced need around him/her to be successful?
— How is the referenced persuaded or convinced? What kinds of motivation does he/she respond best to?
— What is it like to work with the referenced day-to-day? How would you characterize your typical interactions?
— Would you hire or work with this person again? How highly do you regard this person? Top 25%, 10%, 5%, 1%?
(1) I’ve excerpted the questions which I think are most interesting. Tom’s post includes a complete check list of questions, and is worth reading.
(2) “Would you hire or work with this person again?”. This is similar to a question I asked when hiring senior people for Seeking Alpha: “If you were starting your own startup and you needed someone in this role, would you want this person to be part of your team?”.