Thrown out by AIG, Hank Greenberg sues the folks left to mind the store.

The implicit question posed by Greenberg's suit, and one of the great historical questions that looms over the AIG fiasco, is whether things would have turned out differently with Greenberg at the helm. It is not a question with an easy answer.

On the one hand, the accounting irregularities that AIG engaged in on Greenberg's watch are not trivial. It was clearly a company that aggressively pushed the boundaries of what was safe for a giant insurer to do and in some cases went beyond them—AIG paid a $1.6 billion fine to regulators.

Yet on the other hand, tarnished reputation or not, after Greenberg left, and long before the current meltdown, it was Hank Greenberg himself who emerged as one of the fiercest critics of AIG management. "There's no leadership there," Greenberg told Business Week in 2006, a year after he was forced to resign. "The place is run by outside lawyers." You can chalk some of that up to sour grapes, and the argument that AIG's problem was too many lawyers is not really especially convincing. But the blunt appraisal that there was no leadership turned out to be prescient. Having left AIG under a very dark cloud, Greenberg undoubtedly relished the opportunity to turn the tables when he was called to testify before Congress last year about the fall of the company he built.

"When it became increasingly clear that AIG faced an intensifying liquidity crisis, I offered to assist the company in any way I could," Greenberg told lawmakers, "including by raising tens of billions of dollars in private capital. Unfortunately, I was not able to even arrange a meeting with the company to present my proposals." Or, in other words: Hey, I tried to help, and no one would even take my call.

There are certainly enough questions hanging over Greenberg's tenure that no one should be too quick in letting him off the hook. However, it's meaningful that Greenberg left AIG a meaningful amount of time before the collapse. The financial carnival that combined housing insanity with derivatives mania really played for a surprisingly short run: The greatest excesses by far came in no more than three years, from 2005 to 2007. Greenberg wasn't just sent packing before the final explosion. He left before the party really got started.

That's something else that Greenberg shares with Citi's Weill, who left the CEO spot in 2003 after an agonizing and very public search for a successor (he settled on the disastrous Chuck Prince), and Ace Greenberg, who handed off the chairmanship of Bear Stearns in 2001. All three were risk takers with an enormous appetite for putting their companies' capital on the line. Nonetheless, all of them left their houses in something approaching order.