It’s not called the “Not For Long” league for nothing. The NFL is a brutal game that takes an inevitable toll on its players, and the bulk of its rosters are composed of athletes in their early 20s. Many will only see a handful of years before being forced out of the game by injuries, the erosion of skills, and the cost-effectiveness of replacing them with players still on those relatively cheap rookie deals. The Dallas Cowboys are no exception. But a core of senior leaders can be a valuable thing, bringing years of savvy and locker room gravitas.