The simple 28 days moving average method

From the BeyondTEI Yahoo Group:

Buy or hold stocks trading above the 28 DMA and sell stocks going below the 28-d Daily Moving Average.

This method have studied by the Chicago School of Business and explained in the Stock and Commodity magazine. As per the investor Johnamj from the Yahoo BGO board, if you just traded 5 Fidelity Select funds, kept the money in only funds trading over the 28 DMA, on average over a 10 year period you would return about 33% per
year.

Another investor from the BGO board, fcaseymgt, described an experiment he did with the aid of a statician. He tried similar methods with 5 days, 10 days, 15 days, and every plus 5 days until periods of 60 days. He noticed that the best relative performer was the 25-30 day period over all histories 1989-1998. Shorter terms produced noise and longer periods failed at turns.

Even if there were no reason for this method to work, it seems it would have the ability to tell the investor to keep the winners and sell the losers soon.