Correct.  It would certainly be less clear.  When virtually every mill owner chooses not have a spare shaft, one certainly has to wonder whether that is not the prudent course.  In general, it can be quite difficult to determine who is in the "best position" to avoid the untoward event at "least cost."  It can be difficult to answer the questions of what counts as "best" and of how to identify and calculate "costs."    

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