The reasoning behind stripping out a so called common aspect, is to get rid of an unneeded/unwanted extra variable, as well as prevent manipulation of results. a hardcore min maxer would swap out food buffs for certain aspects of the fight, IE hp food at the start, Def/Vit food for heavy physical portions, any sort of magical mitigation food when a big hit is about to come. This over-complicates the test as well as can manipulate results