NEW YORK (TheStreet) -- BlackRock , with $4.52 trillion worth of assets under its watch, knows a thing or two about managing its clients' risk. But the world's largest money manager has also recently shown its prowess in managing its own risk. Flashback to 2009, at the height of the financial crisis, whenaquestions were raisedaabout BlackRock's $13.5 billion acquisition of Barclays' investment unit.