Duke Energy’s leadership fired back at one of its largest investors, Elliott Investment Management, this week after Elliott made a high-profile pitch to break up the energy giant into three smaller regional companies. Elliott proposed the break-up as a means of increasing the overall financial picture of Duke and enhancing shareholder value, which the Florida firm contended was laboring under a “conglomerate discount” in which the sum of the company was not as great as it would be if it were operating three smaller, but more focused and efficient divisions covering the Carolinas, the Midwest, and Florida.