Thanks all.
Don,
You are correct, a search does turn up some interesting reading and spurred my question as I could not find the right weight oils here and knew folks like yourself, who know more than I, would chime in. In general I would agree with you about additives but the zzdp thing seems to have some measure of truth from what I have read. To your point though, I have a Fiero that ran like crap when I used "advanced engineered" spark plugs. I bought them after watching Power Block TV where they showed actual gains with use of them on a dyno. The car runs GREAT on cheep AC Delco copper plugs.
Go figure !?