University of Minnesota did, and is doing a multi year Sulfur study on our home farm.  Its been corn on corn for last five years.   We have never put sulfur on, do get some from hog manure, but is only on 10% of our acres.

Long story short, you could see the plot from the road, nice green squares.  Results from 10 pounds (not sure what source they used, but it was liquid), = 20 bushels and 4 points dryer.

They had another test close by 45 miles down the road on last years bean ground that didn't prove higher yeild, but paid to put sulfur on due to dryer corn.

No doubt on sand it would pay.