Warren Buffett has released his latest annual letter to Berkshire Hathaway shareholders. Since 2012, Berkshire has not repurchased shares at a price higher than 1.2 times book value. According to former investment banker Harvard Winters, this implies that banks and thrifts with ROE far below that of Berkshire buying shares at that book value multiple or higher are acting recklessly. Winters finds three takeaways for banks from the Buffett letter: care deeply about the price of an investment, don’t be overly-optimistic about the future and never assume the bank has an “edge” without empirical evidence.