Drying power is simply a measure of how long it takes for a fabric to dry once sweating ceases. This is also related to lack of saturation. Since Coolcore materials excel at moisture transportation, at the end of the test (or exercise) you are left with a shirt that is uniformly moist but not saturated anywhere, so drying happens quickly.
The WATson machine’s sweating plate is shut off at 70 minutes. At the 80-minute mark the temperature reading shows that the Coolcore material is significantly drier than every competitor. Due to the higher cooling power of the Coolcore fabric during the test, the Coolcore material was evaporating more water, resulting in less overall water that needed to dry at the end of the Cooling Power test.