Gyroscopic Investing

Many prognosticators use January as a barometer for the market upside or downside for that year.  I don't know if anyone has taken the time to check on how often that has been proven true but people do pay attention to that more then many other indicators or at least it gets more press. Do you put any credence in it?

I have noticed that any trend that looks to be working over time gets bought into sooner and sooner by speculators such as metals being stronger in the fall so they start rising in the summer. If you buy in the January effect, perhaps we are seeing early buying now from people wanting to get in earlier.

William Bernstein's opinion: http://www.efficientfrontier.com/ef/799/january.htm.

I can't remember where I heard it but the major moves in December and January have something to do with institutional/hedge fund investors moving in and out of stuff around Jan. 1 for some sort of tax benefit.