Federal Reserve Chairman Ben Bernanke headed to Capitol Hill today for day one of his semi-annual report to Congress on monetary policy. Before the Senate Banking Committee, Bernanke defended the Fed’s highly accommodative policy stance and asserted that the benefits of Fed asset purchases currently outweigh the costs and risks.

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It’s the kind of statement from Bernanke that isn’t exactly earth-shatteringly new, except that last week some investors were reportedly spooked that the central bank might scale back its bond buying program sooner than anticipated. The Dow (^DJI) fell 100 points the day minutes from the last FOMC meeting were released, which revealed more members were concerned about the costs and risks of quantitative easing.

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Zachary Karabell tells The Daily Ticker Bernanke did not allay these policy concerns today, but that’s not necessarily a bad thing.

“It’s good there are people who are expressing concern,” says the investor, author, columnist, and president of River Twice Research. “The fact is no one really knows what the outcome is of this particular set of policies, because there wasn’t like eight times in the 20^th century where you had this thing called QE.”

In other words, there is no precedent for unwinding these unconventional policies. “So no one really knows how this is going to play out going forward and whether or not the Fed will be able to unwind this massive expansion of its balance sheet,” Karabell says.

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That said, Karabell is more sanguine about the risks of easy money policies, and tells us he isn’t losing sleep over any “harbinger of massive inflation” some predict. Karabell believes, compared to other global international players like governments and politicians, central banks have been the better stewards of financial stability.

Yet he’s not without criticism for central bankers.

“One troubling thing about Bernanke, like all central bankers,” Karabell says, “is the hubris of control: ‘We’ve studied the past, we’ve learn the lessons, we know how to mix the levers of the economy.’ That I find troubling, because these are fluid systems and I think everyone should have a degree of humility about their foreknowledge of future outcomes.”

For Bernanke’s part, the Fed chief told members of the Senate panel the Committee remains confident it has the tools necessary to tighten monetary policy when the time comes to do so.