Early planting for your area has a good track record in most university tests, and in several company tests, including Beck's Practical Research Plots in Indiana and Illinois. This year may turn out to be more of a referendum on when corn pollinated and when it received rain, rather than when it was planted.
During the 1983 drought one farmer reported that in the same field he had black ground and higher, lighter ground. He has a soil compaction problem at that time in the lighter ground. The corn in the black ground pollinated a week earlier during a very hot week. It was dry as well. After it finished pollinating, a cool front went through. It brought virtually no rain but temperatures cooled off about 20 degrees. The corn held back and grew more slowly on the lighter soils, and pollinated during the week when it cooled off.
When the combine went through that fall, the black ground made 90 bushels per acre, and the higher ground make 1325 bushels per acre. It wasn't hard to tell why. Pollination was poor and ears weren't filled out correctly in the darker soils that usually yield the best, the farmer notes.
Whether stories like that pop up this year remains to be seen, but the stage is set for similar results. Some of the earliest planted corn pollinated at the end of June and in early July, during the hottest, driest stretch of the drought so far. When no shoots or silks are out and corn pollinates, it doesn't matter how early it was planted- it won't produce corn, at least not much.
The important thing this fall nationwide, at least in the major Corn Belt states that have experienced heat and drought, may not be when corn was planted, but when it [pollinated. Keep that in mind as harvest approaches this year.