As a student of the market, I learned in my early days was that market leadership usually switches from cycle to cycle. That is, during one full bull market—usually lasting three or four years—you usually have one set of leaders from two or three different industries. These industries, of course, are usually the ones with unique, revolutionary products and services that are driving the economy forward during that time … and the companies themselves lead the way. Eventually, the bull dies and a bear market begins, and the leaders generally fall to earth after becoming “over-owned” by the institutional...