The great leaders are like the best conductors - they reach beyond the notes to reach the magic in the players.
Tiger Woods, Larry Bird, Wayne Gretzky, a pitcher just before a game, I would imagine they all have nervous energy. But as you perform, the nervous energy dissipates and you start to relax and you start to do what you do best.
I live in constant fear of being fired or dropped for that dark part of my work I can't control.