One who does is Mr.Cohan, 47, who spent 18 years on Wall Street, including six at Lazard, before setting out to lay bare the secret and frequently sordid workings of his former employer.

• 了解个中滋味的是柯罕，他现年47岁，曾在华尔街工作18年，包括在拉札德任职6年，后来开始揭发前雇主的秘密，通常是龌龊不堪的勾当。