Capturing alpha with beta through commodities

It has been well documented that commodities have had low correlations with other asset classes like stocks and bonds. Perhaps a more powerful statistic, though less well known, is that since 1970, the S&P 500 has on only four occasions posted a negative return for the year was the S&P GSCI negative as well. The years when both indices were down were times of aggregate demand destruction like in the 1980s recession, the tech bubble burst, and the financial crisis. However, during most years, there are fundamental drivers that cause a difference in return patterns between commodities a...