My understanding, this from the mind af a newby in cycling, is that best effecifiency for rolling drag vs traction, vs road contact for a person such as myself, at 150 pounds, and the bike <20 on a 23 tire would call for about 110 psi in the rear and 100 in the front. If I were 200 lbs I would probably be closer t 130 psi in the rear which with many tires are limited to 120 psi. but if you go to a 25, you can lower the pressure. SO if I went to a 25 tire, I could lower the pressure, but I woudl think would give up rolling efficiency as I don't carry the weight, but it would probly be a gentiler ride on a rough road? Notice the question mark! I originally thought the higher pressure the better, but I belive that to be incorrect.
At any rate, I am thinking that at my size, I only need 110 psi max in 23 tires for max effciency, therefore do not need to spend extra money for tires that can handle more pressure. Again, this is from the mind of anover simplified newby.