Historic highs tell you a great deal about the fundamentals of a commodity, in this case corn. How many traders are calling a top and selling this market short? Guess where they are putting their protective Buy Stop orders? Yes, at new highs, so you have short-covering buying pressure at those levels.
Compounding the idiocy of selling historic highs short, as price points they are also important as they represent any “X-Day” high in your system. Whatever that day is, the historic high price point is that price also. Therefore, you’re likely to see new longs enter at those prices too. That’s how markets go parabolic: the shorts are bleeding out of their a**es and the new longs are entering the market.
Historic highs also show you how horrible analysts and talking heads are about making predictions. Trends persist, and those with historic highs can go on for a long time and have several parabolic spikes during the moves.
For more on predictions, you can read Expert Political Judgment: How Good Is It? How Can We Know?. It is one of the most insightful books you can read about human behavior around making predictions.
Here is what Louis Menand from the New Yorker had to say. Most of the reviews echoed his sentiment:
“It is the somewhat gratifying lesson of Philip Tetlock’s new book . . . that people who make prediction their business–people who appear as experts on television, get quoted in newspaper articles, advise governments and businesses, and participate in punditry roundtables–are no better than the rest of us. When they’re wrong, they’re rarely held accountable, and they rarely admit it, either. . . . It would be nice if there were fewer partisans on television disguised as “analysts” and “experts”. . . . But the best lesson of Tetlock’s book may be the one that he seems most reluctant to draw: Think for yourself.”