You should read Tetlock's other work about foxes and hedgehogs in Expert Political Judgment. It presents a theory of why some people are indeed better forecasters than others. It's not lucky or genius, it's more about people who are able to consider several different data points, consider historical precedent, and make a relatively unbiased judgment about what's going to happen. These are the same types of people he sought out for the Good Judgment project, and its these same types of people who were considered Superforecasters making hundreds of forecasts over the course of a year about geopolitical issues.