http://www.rvtiresafety.com/2013/11/interply-shear-and-other-techno-babble.html Check out Tireman9 tire safety website. Eliminates rooky mistakes that we all make about using a minimum pressure from a tire chart in our tires in a trailer position vs tires on our tow vehicles. Apples vs oranges. Trailers can be over tired unlike our trucks.
Tires on a trailer perform best for long term use when properly matched to the trailers GAWRs with say 10-15 percent reserve capacity. This way the tire can be ran at max pressures and doesn't have to be derated.
Now if your the type that runs say 6k-10k in 5-6 years then run the tires the way those that poo poo tire advice if that benefits you the most.
Or if your the type that puts 40k-60k miles on a trailer and expects them to last 5-10 years then pay attention to tire experts/tire engineers like Tireman9 rvtiresafety.com blog.
Spend some time looking at his advice on tire tech for trailers.