Price Discovery

Once the market opens, you have imbalances in buy/sell orders from institutions that use MOO (market on open) orders. Plus, you have a lot of discrepancy between what all the market participants agree the fair value of a stock should be since things may have happened after the market closed the night before and the time the market opens today. So there is heightened volatility during the first 15-30mins while things settle out. That is why you rarely see a trend form prior to 10am. Too much disagreement about where fair value is. But after that part of the morning passes, that is when trends form and price action is more about organic supply/demand. That is why the TT strategy is uniquely positioned to really take advantage of that opening 30mins. You can buy a giant flush and have a reasonable assurance that the probability of a near term bounce are high (vice versa for shorting a rip).