Donald Lindsey has a high-conviction investment idea, and he’s acting on it. As chief investment officer of the $1.2 billion endowment fund at George Washington University, Lindsey isn’t looking to break into an esoteric market or load up on a new product. Instead, he’s increasing the endowment’s allocation to good old U.S. equities: “I still love the asset class,” he says.

Lindsey, who has captained the Washington-based fund since April 2003, points to three trends that make U.S. shares a smart buy. First, earnings have far exceeded expectations: Share prices reached record highs in the second and third quarters of 2011. Because corporate America has done a great job of cutting costs, it’s fattened its profit margins.

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