Since it is done under ASTM D5800 which says the oil is heated to 482°F for one hour with constant air flow over it and weight of oil is measured before and after. I've never seen my engine oil temp reach higher than 223°F even on hot 100°F day in summer. At this temperature the evaporation loss must be way lower? Why should I care about stated evaporation % loss of given oil when it is done at more than twice the max oil operating temperature I observed in my car or does it actually matter?