Net Net: Promoting innovation and managing change
Net Net: Promoting innovation and managing change

Why high-speed trade doesn't really matter to you

HFT & the investor: Who should care?

To the public, the debate over high-frequency trading evokes imagery of high-tech bandits steering machines of mass market destruction aimed at obliterating the investing world as we know it.

In reality, though, the impact is far more nuanced.

Automated traders who move at light speed may be costing big Wall Street firms untold millions or billions in trading-related costs, but the material impact on the mom-and-pop investor is likely considerably smaller. The world of high-frequency trading, after all, usually entails tiny moves in the price of a stock, not major price dislocations for those trying to nibble at Apple or searching for the best price on Google.

As a practical matter, then, the ferocious debate sparked by Michael Lewis' new book, "Flash Boys," is great for water cooler banter about how messed up the financial markets are, but less significant when trying to measure actual costs to Main Street investors.

"The mom-and-pops who have lower profiles have been utterly clueless that any of this has been taking place. They may hear the words 'high-frequency trading,' but it doesn't really affect them," said Diane de Vries Ashley, a corporate finance professor at Florida International University.

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"It does affect portfolios, but it's not visible. It's a hidden cost because you never get to see the true cost of whatever it is you're buying or selling. It's always buried in the commission of some kind. I'm not accusing anyone of obvious obfuscation, but it certainly is easy to not show absolutely every part of a transaction as it goes whipping by."

Read MoreTrader blasts high-frequency trading

Lewis rips open part of that murky trading world in the book, which profiles Brad Katsuyama, a former trading executive at RBC who has made it his life mission to beat the high-frequency traders and expose the way he feels they are manipulating markets.

In an appearance on CBS' "60 Minutes" Sunday evening, Lewis set fire to a weeklong debate when he said the stock market was "rigged" by traders who use computer programs to jump in front of other slower electronic traders to manipulate stock prices.

The accusation has generated heated discourse on Wall Street.

"Are there things that need to be addressed? Absolutely. Is there opportunity for pause? Absolutely," said Art Hogan, chief market strategist at Wunderlich Securities in New York. "But there's a world of difference between 'rigged' and structural inefficiencies. All these things can be addressed. The good news is we're talking about them. Hopefully that brings us to a better place."

The Lewis book is an engaging read. It pulls the audience into a world in which even the people who live in it every day don't fully understand how it works.

Read More7 things learned from Lewis 'Flash Boys' furor

But it's also a familiar tale.

Not all of HFT is bad: Economist

From the time there have been markets there have been traders trying to get an edge over their competitors, and "front running" the market, or trying to figure out what the other guy is going to do so you can push prices higher, is one of the oldest practices in the books.

The alarming part is how secretly and quickly it is being done now. High-profile hedge fund veterans Dan Loeb, David Einhorn and Bill Ackman are quoted in the book saying they didn't realize the computers had been able to blow a hole in markets.

Yet unanswered is just what this costs investors outside the world of testosterone-filled traders trying to outbid and outdo each other.

The most obvious way would be through large pension funds and mutual funds. Theoretically, the firms handling those accounts could get caught having to pay higher prices than they would in an HFT-free market, driving up costs for individual investors counting on their pensions and 401(k) plans.

Read More'Unfair' markets only impact day traders: Cramer

In practice, though, the largest firms in the fund business say that's simply not happening.

"The overall cost of investing in the equity market has actually come down significantly due to changes in regulations, technical enhancements and increased competition," said Katie Henderson, a spokeswoman at Vanguard, which manages $2.75 trillion for clients. "Vanguard has realigned its trading practices over the years to mitigate adverse impacts of trading costs."

Henderson said the firm encourages regulators to keep looking at ways to weed out "disruptive trading" but believes most high-speed traders operate within market rules.

An executive at a another big fund firm said the industry actually welcomes the HFT presence as it helps provide liquidity and price discovery—familiar arguments in favor of the high-speed traders.

It's also a position that Gary Hager, president of Integrated Wealth Management in Edison, N.J., believes holds true. One of Hager's clients is an unnamed high-frequency trader who got in around the ground level in 2004, and he believes that the market actually would be mourning its losses should HFT go away.

"If HFT was further regulated, and I'm not sure how you do that, it could have a negative impact on the public's perception of the market," Hager said. "What would happen is if that was curtailed, restrained or eliminated, the amount of volatility that would be added to the market would be more than the average investor would be comfortable with."

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Interestingly, he agrees with Lewis' comment that the market is rigged, but believes it is more so by the big Wall Street investment firms than by smaller HFT operations.

For the public, the raging debate over rigged markets is likely to stoke even more skepticism about Wall Street and the financial markets, something that could be costly should they decide to avoid stocks and the high-frequency trading sideshow.

"It kind of shows that the Street outsmarts itself sometimes. I'd love for it to be a be-all end-all scandal, but I'm not quite sure I see that," said Ashley, the Florida International professor. "It appears at least in my memory that everybody who is in that business does exactly the same thing, and that some of the institutions aren't totally unhappy with that. This is a hard one to unravel.

"It's more people having a gut reaction that something smells. But they're not sure if it's a stench, or just a bit of malodor."