For members, I maintain rankings of Fidelity Select Funds by relative strength. The performance over the last 25 years or so has been exemplary with risk adjusted annual returns in excess of 12% and 13% (depending upon the number of funds rotated). The problem with this method is the draw downs can be quite severe at times, and I am aware of the public's propensity to panic at bottoms. Attempting to utilize a market timing technique based upon a major market average actually worsened performance; reducing the returns with even larger draw downs.
Reason: markets top and bottom Sector by sector. A sell signal may have occurred on a major average but our sector long position did not top, even advanced for awhile longer. That gain was lost due to the major average sell. A buy signal and buying the top ranked found that they had already moved a bit. Conclusion follow sectors and not the major averages.
Sector Watch: I have found over the years that stocks in an Overweight position surprises tend to the positive side. Those with underweight the reverse. If you are a bull look to buy the over weights, a bear look to short the under weights.