Recently there has been talk here that 5W20 base stock may provide better short trip protection due to lack of VII's contained in thicker 5W30 which are heat activated . *It occurs to me that Europeans short trip as well as Americans - yet they are still recommending 5W30 weight oils (or thicker) in most situations ... What gives here ? Does a "grocery getter " with 5W20 printed on the oil cap using say M1 5W30 versus M1 5W20 going to really be any less protected on under 5 mile trips ?