Tow vehicle tire pressure

I purposely pump up my tow vehicle tires to just under the highest tire pressure allowed that shows on the sidewall of the tire to give more stiffness in the handling to alleviiate sway in the whole rig, I tow a tow behind camper and the tires are a passenger rated tire at 45 lbs max. It seems to help with the towing stability, Just wondering what other folks do and if the extra pressure really makes much difference with passenger tires and their softer sidewalls??