After trading slightly lower overnight, corn and soybean prices both encountered enough buying about midway through the day session to carry them to gains of 5 cents or more at the close. However, the reverse was true of the wheat markets. General Comments Trading volume overnight and during the day session was light as befits the day before USDA's December WASDE. In the absence of new production estimates for corn and soybeans, the market does not expect any major changes in U.S. or world supply/demand estimates. Thus, traders do not have much to prepare for by way of positioning that they have not already done. In general, none of the expected tweaks in supply/demand estimates are going to change the overall theme of ample U.S. and worl...