I don't think I have forgotten the origin of this discussion. I am simply saying, at the outset, and in expanded comments, that running an engine in today's conditions, given all the improvements in peripheral factors, without an oil filter, as compared to operating with a by-pass filter, will have no significant adverse affect on engine life when operated as the OP described. Further, I maintain that continuously filtering the the entire oil supply with a full flow system is a superior method of filtration when compared to the by-pass method. Were that not the case, all of the modern automotive, construction and other industrial lubrication and hydraulic systems would not be using full flow method. If one could add some inert colored matter to an oil supply and run engines of otherwise identical spec, but for the filter method, I submit it would graphically illustrate how much more quickly and thoroughly the "contaminants" would be removed by the full flow system. Unfortunately, I do not have the means to actually run such an exercise and test my belief, So, I am going to have let my comments stand on their own and any interested parties can determine their own conclusions.