I’ve posted Entry #7 in my weekly Valuation-Informed Indexing column at the Value Walk site. It’s called The Real Reason Why Short-Term Timing Doesn’t Work.
Juicy Excerpt: It could be that short-term price changes are unpredictable not because the market is highly rational but because it is highly irrational. You can’t beat the market if it is so rational that you cannot get an edge. But you also cannot beat the market if it is so crazy (in the short term) that all the analysis in the world does not give up a clue as to where it is headed.