What is important for giving no damage to tires, is that not any part of rubber of tires goes over a sertain temperature.
The inside tire temperature shal be in line with the temperature of rubber. Not totally but asume it is for sakes of simplicity.
Lets asume that when inside tire temp is 160 degr F. that then the hottest part of rubber wont reacht a temp at wich it hardens ireversible.
Then when filled AT 50 psi at 65 degr F , it will be at 160 degr F 61.7 psi. 61.7/50=1.234 so rise of 23.4%
Filled at 110 psi at 65 degr F it will rise to 132.6 psi at 160 degr F .
132.6/110= 1,2055 so rise of 20.55%
lower pressure used in normal car tires even gives more % rising when going from 65 to 160 degr F .
Mayby this is why these high percentages are given officially , because those count for pressures of 35 psi to give the tire inside a temp of that 160 degr F.
This 160 degr F is my estimation so dont see it as an exact number, only to prove the different percentages for filed cold pressure.
And ofcource its much more complicated proces. when higher ambiënt temp cooling down of tire is worse but then cold pressure is also higher wich gives lesser deflection so lesser heatproduction.
Better is to give the tire lesser deflection then the critical border sp tire inside wont reach that 160 degr F .
But to high pressure gives discomfort and bad gripp.
I determined that when pressure is the right balance so with some reserve, that then when ambiënt temp is 65 degr F, and driving about 50m/h , the tire inside will reach a temp of about 110/115 degr F.
And when you then calculate the pressure rising in percentages, it will be about 10 to 11% depending on hight of filled cold pressure.
So also my conclusion is that 10/11% is the goal when driving 50m/h.
Then you still have acceptable comfort and gripp.
An ST tire is calculated in maximum load for the AT-pressure for speed of 65m/h.
So using that given maximum load when calculating needed pressure, the tire has more deflection then an LT tire wich is calculated for 99m/h.
By that more deflection more heatproduction at the same speed, so hotter inside tire temp.wich gives higher percentage of pressure rise.
But also for an ST tire its better , the inside tire only reaches that
110/115 degr F when driving 50m/h . so rubber also stays way below the
critical temp, and then comfort and gripp yust as acceptable as the comparing LT tire.
