Cash -- Thanks for the link. The introductory paragraph prior to the list of rules changes is hysterical! I guess we are all victims of Katrina. LOL http://www.sec.gov/news/digest/dig091505.txt "SEC NEWS DIGEST Issue 2005-178 September 15, 2005 RULES AND RELATED MATTERS SEC APPROVES REGULATORY RELIEF AND ASSISTANCE FOR HURRICANE KATRINA VICTIMS On September 15, the Securities and exchange Commission today an order providing emergency regulatory relief to investors, companies, and securities firms affected by Hurricane Katrina."
The thing with the imbalances is that it intensified the edge. And on top of that, some imbalance stocks would often open with little or no gaps. It was basically a great opportunity to press your bet.
I was told by a friend on the floor that by the time the imbalance is posted a contra party is already involved. Was an edge ever there?
I think it has to do with the SPX settling on the Friday opening print. Maybe traders have figured out how to manipulate OP's in the SPX