Any Bank of America (NYSE:BAC) investor or banking-sector fan knows that Bank of America's acquisition of Countrywide will go down as one of the worst of all time.

The mortgages written by Countrywide ultimately became responsible for billions of dollars of legal expenses for Bank of America. But how much worse were these loans? Matt Koppenheffer details these loans in his article "The Great Undoing of Bank of America."

In this video, Matt joins Motley Fool banking analyst David Hanson to discuss this article and tell investors the key takeaway from the multiyear debacle.