After Sotheby’s announced their last quarterly financial statements, CEO Bill Ruprecht explained that “We believe that these results validate our strategy, demonstrate the significant operating leverage in our business model and highlight our ability to execute in a strong market”. With a robust 12 month income of over $170 million dollars on sales revenue of $807 millions dollars, he should be crowing.  But read this boast carefully.   These results mirror a key aspect of the Sotheby’s/Christie’ duopoly, namely the “significant operating leverage” their business model has been able to maintain.  That leverage has many factors that are inherent with an advantage that no one or group of concerns in…