America has been learning a lot lately about “the Bain way.” The damning 28-minute video “When Mitt Romney Came to Town,” put out by a pro-Newt Gingrich super PAC, and the new book “The Real Romney,” by Boston Globe reporters Michael Kranish and Scott Helman, have shed light on the strategies that Mitt Romney’s old private-equity firm, Bain Capital, used to generate outsize returns for its investors.

Make no mistake: Under Romney’s leadership in the 1980s and 1990s, Bain was a top-performing private-equity fund. According to an internal 2000estimate, the fund achieved annualized returns of an astounding 88 percent from 1984 to 1999 for its institutional investors, including state and corporate pension funds that invest the savings of millions of American workers. It also made a fortune for Romney, whose net wealth reportedly exceeds $250 million.

For Kranish and Helman, the Bain way is an “intensely analytical and data-driven” approach to studying companies, what makes them successful or not, and how to boost their competitiveness.

The video “When Mitt Romney Came to Town” is understandably less sympathetic. To the filmmakers, bankrolled by the Winning Our Future super PAC, the Bain way is nothing less than “turning the misfortunes of others into . . . enormous financial gains.” The film spends most of its time interviewing people who lost their jobs and much of their savings after working at various companies that Bain bought, milked and sold to generate those huge profits.

Yet, there is another version of the Bain way that I experienced personally during my 17 years as a deal-adviser on Wall Street: Seemingly alone among private-equity firms, Romney’s Bain Capital was a master at bait-and-switching Wall Street bankers to get its hands on the companies that provided the raw material for its financial alchemy. Other private-equity firms I worked with extensively over the years — Forstmann Little, KKR, TPG and the Carlyle Group, among them — never dared attempt the audacious strategy that Bain partners employed with great alacrity and little shame. Call it the real Bain way.

Here’s how it worked. Private-equity firms are always eager to find companies to buy, allowing them to invest chunks of the billions of dollars entrusted to them and from which they earn hundreds of millions in fees. One ready source of these businesses is Wall Street bankers hired to sell companies through private auctions. The good news is that when a banker puts together a detailed selling memorandum about a company, chances are very high that company will be sold; the bad news is that these private auctions tend to be very competitive, and the winning bidder, by definition, is most often the one willing to pay the most. By paying the highest price, you win the company, but you also may reduce the returns you can generate for your investors.

I never negotiated directly with Romney; he was too high-level for any interaction with me. Rather, I dealt often with other Bain senior partners, who were very much in his mold. In my experience, Bain Capital did all that it could to game the system by consistently offering the highest prices during the early rounds of bidding — only to try to low-ball the price after it had weeded out competitors.

By bidding high early, Bain would win a coveted spot in the later rounds of the auction, when greater information about the company for sale is shared and the number of competitors is reduced. (A banker and his client generally allow only the potential buyers with the highest bids into the later rounds; after all, you can’t have an endless procession of Savile Row-suited businessmen traipsing through a manufacturing plant if you want to keep a possible sale under wraps.)

For buyers, the goal in these auctions is to be one of the few selected to inspect the company’s facilities and books on-site, in order to make a final and supposedly binding bid. Generally, the prospective buyer with the highest bid after the on-site due-diligence visit is selected by the client — in consultation with his or her banker — to negotiate a final agreement to buy the company.

This is the moment when Bain Capital would become especially crafty. In my experience — which I heard echoed often by my colleagues around Wall Street — Bain would seek to be the highest bidder at the end of the formal process in order to be the firm selected to negotiate alone with the seller, putting itself in the exclusive, competition-free zone. Then, when all other competitors had been essentially vanquished and the purchase contract was under negotiation, Bain would suddenly begin finding all sorts of warts, bruises and faults with the company being sold. Soon enough, that near-final Bain bid — the one that got the firm into its exclusive negotiating position — would begin to fall, often significantly.

Of course, some haggling over price is typical in any sale, and not everything represented by sellers and their bankers is found to be accurate under close examination. But Bain Capital took the art of negotiation over price into the scientific realm. Once the competitive dynamics had shifted definitively in its favor, the firm’s genuine views about what it was willing to pay — often far lower than first indicated — would be revealed.

At such a late date, of course, the seller is more than a little pregnant with the buyer. Attempting to pivot and find a new buyer — which knew it had not been selected in the first place, but was now being called back — would be devastating to the carefully constructed process designed to generate the highest price. Once Bain’s real thoughts about the price were revealed, the seller either had to suck it up and accept the lower price, or negotiate with a new buyer, but with far less leverage.

Needless to say, this does not make for a very happy client (or a happy banker). By the end of my days on Wall Street in 2004, I found the real Bain way so counterproductive that I no longer included Bain Capital on my buyer’s lists of private-equity firms for a company I was selling.

The real Bain way may be nothing more than a clever tactic to eliminate competition from a heated auction in order to buy a business at an attractive price. After all, Bain Capital is seeking the highest returns for its investors. But Bain’s behavior also reveals something about the values it brings to bear in a process that requires honor and character to work properly. If a firm’s word is not worth the paper it is printed on, then its reputation for bad behavior will impair its ability to function in an honorable and productive way.

I don’t know if Bain Capital still uses the bait-and-switch technique when it competes in auctions these days (I’m told that it doesn’t). But that was the way the firm’s partners competed when Romney ran the place. This win-at-any-cost approach makes me wonder how a President Romney would negotiate with Congress, or with China, or with anyone else — and what a promise, pledge or endorsement from him would actually mean.

Would a President Romney, along with a Republican Congress, cut taxes for the wealthy even more than he has pledged to do? Would he not try to balance the federal budget, even though he has said he would? Would he protect defense spending, as he has indicated he would?

I have no idea how Romney might behave in office. I do believe, however, that when he was running Bain Capital, his word was not his bond.

wdcohan@yahoo.com

William D. Cohan, a columnist for Bloomberg View, is the author of “Money and Power: How Goldman Sachs Came to Rule the World” and “House of Cards: A Tale of Hubris and Wretched Excess on Wall Street.” He has worked at Lazard Freres, Merrill Lynch and J.P. Morgan Chase.

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