(FORTUNE Magazine) – We must live in a great country when two entities as unlovable as H.J. Heinz and Nelson Peltz can butt heads and produce a result that's good for millions of people. But it happened. It's a nasty, ugly saga that gives me hope for America's future. As you surely know, Heinz and Peltz recently concluded the highest-profile proxy fight in years. Since both sides put out deceptive arguments for their case, let's remember a few basic facts: Heinz CEO Bill Johnson and his team have done a lousy job since taking over in 1998, despite their loud insistence to the contrary. Total return to shareholders was --11%, vs. the S&P 500's 14% rise, from Johnson's ascension until February, when the stock jumped on rumors of an activist's involvement.

This is a management team that needed a kick in the pants, which Nelson Peltz gave them. The Palm Beach billionaire and his associates accumulated 5.5% of the company (more than any member of the Heinz family). He then announced his plan for fixing Heinz and launched his campaign to replace five of its 12 directors with his own candidates, including himself. Results haven't been announced as we go to press, but early indications are that some of Peltz's candidates may have won, though shareholders probably didn't elect his entire slate.

When Peltz attacked, Heinz's leaders responded in the classic style of entrenched managers who value nothing more than their own jobs: Suddenly energized, they launched a special website featuring derogatory press mentions of Peltz. They also visited major shareholders with a PowerPoint presentation showing how they were doing a great job--and how Peltz and his crew were very, very bad.

Then something interesting happened. While Heinz managers blasted Peltz's plan for fixing Heinz as "superficial and unrealistic," they started to ... adopt it. Peltz wants Heinz to cut administrative expenses, reduce trade deals and allowances, spend more on marketing, increase its share buyback, and raise the dividend. While kicking and clawing at Peltz with all its might, Heinz has decided--based strictly on its own judgment, mind you--to do every one of those things. It isn't doing everything to the extent Peltz wants, but the direction is clear.

More important, Heinz stock has shown its first signs of life in years, rising 23% since Peltz got into the act.

So this Peltz must be some hero, huh? I'm afraid not. He has a 20-year history of financial prestidigitation that always leaves him richer but does not always benefit his own shareholders. The Corporate Library, which grades companies from A to F for shareholder friendliness, gave Peltz's company Triarc an F for years (recently raised to a D because of an across-the-board grading change). That's partly because Triarc uses two classes of stock through which Peltz and his associates control the company and make sure no one does to them what they're doing to Heinz. Peltz's pay has also been abusively high.

Ben Stein, the financial writer (and actor), wrote a landmark analysis of Peltz's rise in 1989. I asked him what he thought of Peltz today. He replied, "Trusting him to help the ordinary stockholders is like trusting Dracula to run a blood bank, based on what I saw in his earlier life. Then again, this is just my opinion and could be totally wrong. But you tell me, how many times does the leopard change its spots?"

You could lump this drama with today's wave of private-equity buyout deals, but it's actually much less trendy--and that's what I find encouraging. Peltz, like Carl Icahn and others, is an old-school financial buccaneer just doing what he does. And 20 years from now others will be doing the same. That's how our markets work, and despite capitalism's global spread, there still aren't many places where financial markets are so wide open legally and culturally. I can't find anybody to like in this story, yet Heinz's shareholders--not just Peltz but also the retired schoolteachers and factory workers whose pension funds hold the stock--are $2.5 billion richer.

So how should Heinz's shareholders regard Peltz? My advice is, Grit your teeth, hold your nose, watch him like a hawk--and thank him.

FEEDBACK gcolvin@fortunemail.com