Bank of America was once Berkshire Hathaway's second-largest position, but Buffett has sold about 25% of it so far.Few investors' moves and comments draw as much attention as Warren Buffett's -- and there's good reason for that. He has a track record nearly 70 years long of producing market-trouncing returns for shareholders. Not only that, but he manages over $600 billion of investable assets for Berkshire Hathaway (BRK.A 0.84%) (BRK.B 0.65%), which is a lot of weight to throw around.So, whenever Buffett's ...