I would like to ask a question. How many people have modified their truck? Chips? How many people have put LT tires on a 1/2 ton truck when the tire placard on the door lists the size in 'P'? Or gone up in tire size? Truck/Car manufactures recommend genuine 'GM', 'Ford', 'Dodge' or Toyota parts and yet we use other brands.
Most of us want the best for our vehicle/trailer with what our wallet can afford. Companies want to maximize profits and that means, at times, just meeting specs. Governments low bid and so do companies of all sorts. How many use a full synthetic engine oil when it is not necessary? Why? Because we think it is better. The same for putting LT tires on a trailer. Why? Because some think it is better. Is it? I am inclined to think so as long as it meets or exceeds the load specs. I have yet to see anything posted anywhere over the years that makes me change my mind.
I have been in the automotive business (mechanic) for almost 40 years and I sure don't believe everything a vehicle manufacturer tells me, just like I don't believe everything the government tells me. Remember the Ford Explorer/Firestone debacle a decade and a half ago? Both companies pointed fingers at one another.
Another example: A few years ago a tire company recommended to police officers and fleet mechanics that the police tires be inflated to 52 psi on the Crown Vic patrol vehicles. We tried it and the reports from the police was almost immediate. No traction. Lowered the pressure and problem fixed.
That being said, I recently upgraded my tires from ST205/75/14 to ST205/15/15 'D' Maxxis. I really wanted use Goodyear HT LT215/75/15 but I was concerned about availability on the road. ST205/75/15 tires are available most everywhere. I judged that going up in load range and using Maxxis was a considerable improvement over what I had. That is the bottom line - improvement and peace of mind.