Yeah Goodyear offers this advise for all trailer owners (rv and non rv)....
Goodyear Tire and Rubber .... weighing RVs
Special Considerations
**Unless trying to resolve poor ride quality problems with an RV trailer, it is recommended that trailer tires be inflated to the pressure indicated on the sidewall of the tire. Trailer tires experience significant lateral (side-to-side) loads due to vehicle sway from uneven roads or passing vehicles. Using the inflation pressure engraved on the sidewall will provide optimum load carrying capacity and minimize heat build-up.**
Of course their thinking is most folks don't over tire their trailers such using a ST G at 4080-4400 lbs capacity on trailers with 6k axles and 2800 lbs per tire loads.