Demand for U.S. corn and wheat isn't strong enough to change anything, at least not today, although  soybean demand could make a difference. The domestic crush hasn't slowed, and U.S. origin is now reportedly competitive with South America.Last week's USDA crop production and ending supply estimates left little for the bulls to trade, at least through the balance of August and probably until the 11 September updates and WASDE revisions. The fact the USDA raised the corn and soybean yield estimates to their second-highest levels ever caught most in the market by surprise, although significant yield reductions weren't anticipated. In fact, the market wouldn't have been surprised if the yield estimates had been left unchanged. WPI has wri...