4 1/2 or 5 quarts of oil with 1/2 quart of ZZDP?

Some of you younger guys may think I am nuts but with me being ole school in Mopars, for the last 30+ years I have been adding a bottle of STP, which contains Zinc, at every oil change and to this date I have had not 1 problem with any internal parts running metal on metal or any internal parts failing.