You don’t have to own a set of Quarq’s TyreWiz to take advantage of the updated and improved pressure measuring app. SRAM made a few updates to their Recommended Tire Pressure chart. The update includes more options to let you refine the recommended tire pressures to the dimensions of your specific set up.
One thing that everyone should experiment with is to try changing the rider weight and see how little it affects the pressure. On the other hand, if you change the volume (tire size or inner rim width) it dramatically alters the recommended pressure. If you have an older wheelset they will likely have a very narrow internal width. This results in a system that has reduced volume leading to the need for higher pressure.