The slow growth of western economies, and the moods of greed and fear that grip modern markets as they lurch from ‘risk on’ to ‘risk off’ make the task of providing good investment advice ever more difficult. Bull markets used to outlast and outpace bear markets. Advisers used to say if you bought and held US or UK shares from whatever start date you would make money over five or 10 years. That no longer holds true for some recent periods.