As shares of Berhshire Hathaway Inc. (NYSE: ), ( ) plunged over the past year, it became fashionable to ask whether or not Warren Buffett had lost his touch.

(See: ETF Guide: Down $16 Billion - Has Warren Buffett Lost His Touch?; MSN Money: The problem with Warren Buffett; Forbes: Has Buffett Lost His Touch; Reuters: Is Warren Buffett losing his touch?)

In June, financial advisor and CNBC contributor Dennis Gartman even called Buffett “an idiot.”

But now that Berkshire has rallied more than 35% from its March lows, the only idiots to be found are those that ever doubted the world’s second-richest man’s business savvy. Indeed, many of the moves Buffett made during last year’s market melee are paying off in a big way.

Take, for instance, his $5 billion investment in Goldman Sachs Group Inc. (NYSE: ). Berkshire last September agreed to buy $5 billion in perpetual preferred Goldman shares that pay 10% interest.  In addition, Berkshire received warrants giving it the right to buy $5 billion worth of Goldman’s common shares at any time over the next five years at a price of $115 per share.

Critics lampooned that deal when shares of Goldman Sachs fell to a 52-week low of $47.41 in November. Since then, however, Goldman’s stock has rocketed more than 240% to close yesterday (Tuesday) at $160.25.

If Berkshire cashed in it’s warrants today, it would make a 40% profit or about $2 billion.