He highlighted the risk of bonds and emphasised the importance of sticking with a simple investment strategy. : He highlighted the risk of bonds and emphasised the importance of sticking with a simple investment strategy Seattle — Sometimes the best lessons are worth repeating.Billionaire investor Warren Buffett used his widely-read annual letter to Berkshire Hathaway Inc. shareholders on Saturday to again call out the wasteful fees that many money managers charge. He highlighted the risk of bonds and emphasised the importance of sticking with a simple investment strategy.“Performance comes, performance goes,” Buffett wrote.