The most intriguing role in the Hewlett-Packard drama that might now be called The Education of Mark Hurd does not belong to Jodie Fisher - the woman at the center of HP’s ethics scandal.

Instead, it belongs to HP’s CFO, Cathie Lesjak, who is now serving as the technology company’s interim CEO.

HP said that its board asked its CEO to resign in large part because of expense irregularities uncovered during an investigation prompted by the board receiving a June 29 letter from Ms. Fisher. In the letter, Ms. Fisher accuses HP’s CEO of sexual harassment.

The board’s decision stunned Silicon Valley watchers and has stirred debate among corporate-governance experts who have questioned whether the board acted too rashly.

Lesjak’s ascendance to the top finance role came less than two years after Hurd’s 2005 arrival and immediately produced a CEO/CFO ticket with insider credentials. As a 24-year HP veteran, Lesjak was well-known to the board, and she was not expected to move only within the limits of her new CEO’s shadow.

The resignation is “all about Mark’s behavior and judgment” she told reporters during a hurriedly arranged Friday afternoon call with the media. So much for CEO/CFO lockstepped relationships.

“Deep and trusting” are the words we so often hear applied to successful CEO/CFO relationships. In fact, the golden rule of successful CFOs has long been “build a strong relationship with your CEO.”

Last Friday, HP’s Lesjak put her own spin on it: Keep your CEO close, and your board closer. ###