Perhaps an additive is good for users that only use a few gallons per year and the tractors set around for months between tank refills. I don't know of any farmers who use thousands of gallons of fuel per year who add any thing to their diesel. My retired brother in law does maintenance for a super large farmer who last year was burning $100,000 of fuel per month. They don't add anything to it and he said they have never had a failure in fuel system. They put thousands of hours a year on each machine which is likely more than any 10 CUT owners will put on in a lifetime.
As I have said many time, put whatever in your fuel tank and oil reservoir that makes you rest easy at night.