Resolving whether Apple Inc. (AAPL) can stand as the world's most powerful consumer electronics company as long as competent people are at its helm, or whether its success depends on the irreplaceable genius of a few key individuals, is a critical question for investors to answer. If the influence of these individuals is overstated, then investors could lose money in a useless panic when a specific individual retires, moves on to another job, or dies. Conversely, if these individuals really are indispensable to the tech firm's success, then watching them closely is a rational guide to investment decisions involving the California company's stock.