Many believe that the bulk of engine wear occurs at startup. Here's a link that suggests it's due combustion byproducts/acid, rather than metal-to-metal contact http://www.fernblatt.com/longhurst/additives.html Does this have merit? If not - if it's more metal-to-metal contact causing the wear - would the basestock play more of a protective role during the startup period, as the AW/FM won't be activated until moderate-to-higher engine temps are reached? Altho ZDDP (apparently activates at lower to moderate temp), moly (higher temps), boron (what temp does boron activate at?) may have gone thru an "uptake" process by the metal, will they not become "plastic" until heat activated? So would startup protection be subsequently relegated to the basestock properties?