Now Gerstner is trying to buff his image with a book about how he turned IBM around. Like its author, the book is unusual, starting with its cover. Look at it. Normally, a star author like Gerstner looks you straight in the eye. But Gerstner is staring off the cover, and you see a lot of desk and window. This would get an F in Cover Design 101. What happened? Gerstner, an IBM spokesman says, hates being photographed, but liked his picture in an old annual report. End of story.

This stubbornness and single-mindedness stood Gerstner in good stead from the day he showed up for work at IBM in 1993 (he had to bang on the door to get in–he had no building pass). IBM and its moneymaker, mainframe computers, seemed doomed. When he stepped down as chief executive in March–he’ll leave the company at the year-end–IBM was hugely profitable and its future was as assured as any computer company’s can be.

Gerstner may be a great CEO, but he’s not a good writer. Even for a business junkie like me, the book is tough sledding. It feels assembled, like a computer, rather than written. Gerstner fills entire pages with his old letters and presentations. In addition, there’s a 56-page appendix consisting of his letters. And trust me: when it comes to writing letters, Gerstner is no Warren Buffett.

But if you force yourself to read the book, you find treasures lying on the cluttered forest floor. Gerstner’s “elephants can dance” observation of the title–that big companies can outmaneuver small companies because they can afford experiments that fail–is counter-intuitive, and terrific. So is his insight that computer systems typically aren’t user-friendly because most companies are run by techies who don’t think about what it’s like to be a computer customer.

Gerstner’s biggest accomplishment is transforming IBM from a company that sold computers and software into a company that solved problems for customers by integrating computer systems. That’s now its biggest and most lucrative business. He was also an early embracer of the Internet. But how did he come up with these ideas? What blind alleys did he go down? He doesn’t say.

Gerstner doesn’t deal with the biggest question mark on his record: that he seems to leave jobs at just the right time. Financial problems appeared at RJR Nabisco soon after he left to join IBM. Shortly after he left American Express to join RJR, the business he was in charge of ran into trouble. And at IBM, his successor as chief executive officer, Sam Palmisano, dialed back Gerstner’s optimistic estimates almost before Gerstner’s chair had cooled.

The stock market, though, has few doubts. IBM’s stock rose almost 700 percent during his tenure, 4.5 times as much as the market as a whole. Lots of this comes from his new strategies–but a substantial part comes from playing financial games. IBM spent more than $30 billion from 1997 through 2001 to buy back its own shares. This vast sum, more than enough to repay the company’s entire debt, was used instead to prop up its share price short term. IBM benefited hugely last year from fluky accounting rules involving pension funds. Aggressive assumptions on how much its pension funds would earn helped IBM report $1.3 billion of pretax profit, even though the funds actually lost $4 billion. The total of the two was equal to almost half the company’s pretax profits.

Gerstner could have said that given Wall Street’s idiotic imperatives, you sometimes have to play idiotic games to make the numbers come out right. That would add to his image, not diminish it. But that would be admitting error, and seeing the world in shades of gray. Gerstner doesn’t do this, at least not in public. So he ignores the topic.

Gerstner says he’s unlikely to write another book. I hope that the ego gratification he’s getting from this one leads him to write a sequel. Maybe then, the cover–and the contents–will look us squarely in the eye.