Based on what I’ve observed in football and elsewhere, leadership is a product of preparation and instincts. The Manning QBs obsess over preparation, especially Peyton, who might be the best ever at dissecting opponents pre-game, then adjusting his offense in the heat of battle. Eli has inherited enough of that to be elite. Both Coughlin and Belichick preach preparation for their fairly sophisticated game plans.
But preparation will only go as far as your instincts will take you. Early in his career, Eli either didn’t have the instincts to recognize what he prepared for or didn’t have the confidence to trust that he was making the right calls. Those days are over, and he’s super-confident — undoubtedly elite — and the possessor of two Super Bowl rings.
I could make a strong argument that preparation is the result of hard work — a personal commitment to strive toward excellence — while instincts are the product of experience and self-awareness — a personal commitment to persevere through adversity and learn from mistakes and successes.