OK...here's a question for the "real" experts. As long as an oil's insolubles aren't excessive, TBN value still acceptable, and there's no glycol, fuel, water in it, i.e., the add pack isn't terribly depleted, what harm is being done to the engine if the wear metal values are on the high side? If I understand correctly, the wear metals being measured in a UOA are less than a micron in size and are essentially in solution and are in the parts per million type quatities. I understand that high values indicate problems for an engine already broken in. But will high values cause problems in and by itself over the short run?