If your opponent has an exposed king it is frequently worth sacrificing a pawn to be able to bring your rooks into the game, especially if your opponent's rooks are languishing in the corner. Kasparov has made a career out of such sacrifices.

Even in the King's Gambit ... White is no longer trying to attack at all costs. He has had to adapt his approach and look for moves with a solid positional foundation ... As often as not, his strategy consists of stifling Black's activity and then winning in an endgame thanks to his superior pawn structure.

... on the right occasion a bold choice of opening can unnerve even the most steely opponent.