Could soil compaction ever help yield instead of hurt it? It did in one documented case, but it was a fluke. However, this just might be a fluke year. Nothing has been normal in the weather department so far, what with the wettest April since 1895 and the hottest spell in July since 1988. In fact, my copy editor actually called me to ask me if I meant 1995 instead of 1895. No, it was 1895, at least in Indiana and much of the Eastern Corn Belt.
Now here's that case where soil compaction actually added 30 bushels per acre. It was a wet spring, although nothing like this one, conventional tillage was still used, and part of the ground was dark and black, usually the best ground, while the rest was the lighter ground, still fairly good ground, although also with a drainage problem. High spots is relative, there were no hills in this field.
When the combine went through, the lighter ground where the soil always packed tighter was kicking the pants off the black ground, by 30 to 40 bushels per acre. The farmer scratched his head, then tried to put the pieces together. As it turned out, the black ground pollinated during the very hottest week of the summer. It wasn't as hot as it is now, but it was hot enough- definitely not ideal for pollination.
Because the corn on the lighter spots had compacted roots from working the soil wet- the farmer can't be blames- Gary Steinhardt of Purdue University hadn't started talking about soil compaction yet as an evil of the corn bean and no forage rotation- that corn was about a week behind. It was stunted by the compaction and slower growth due to a limited root system.
Guess what? The next week when that corn finally pollinated, it cooled off considerably. The corn pollinated in good shape, and had much better kernel set than the corn in the black ground.
So is the message go out and compact your soil? No- it could have worked out to be just the reverse. The message is to be observant, and try to explain what you find. This wild ride of a weather year should provide plenty of chances to search for answers to questions.