I've mentioned in the past that the only large losses with the COT have come on the short side. Here is the last one. In Mar. of 03 the commercials went long almost exactly at the beginning of this bull market. Then at the end of June they reversed to a huge short position in one weeks time. I suspect they thought the rally was just going to be a short counter trend affair. When the market didn't start to head back down they quickly figured out something was different and removed the large short position towards the end of Sept. So yes the COT does get it wrong from time to time. However unlike the emotional retail trader when the big boys are wrong it doesn't take them to long to figure it out and fix the problem. This is why I'm careful when I take a COT short signal. I want as many odds in my favor as possible before shorting the market.