What does it mean? I think it means exactly what it looks like. Most of these people don't know crap.....in a room full of traders some will look like geniuses, some like losers...the rest somewhere in the middle. Tons of studies like this have been done with similar random results. In an efficient market you will find results that fit right into a standard bell curve of standard deviation. Traders fall into this curve as well.
bell_curve.gif
It may be a crap shoot...but at least it is a crap shoot where you get to decide which side of the table you want to sit on. Reducing cost basis and improving exit in efficient markets are statistically proven ways of gaining an edge.... ie....be the house instead of the gambler.

Because what Blain said is probably accurate you could almost fade these so called experts and do just as well or better....especially using cost basis reduction strategies on top of it.