Our initial hot end design included room for dual nozzles, heaters and thermocouples.  Below are a few images highlighting that early design during assembly and testing.  The design has now been refined into a single nozzle yet keeps the same functionality of a dual extruder hot end.  We were able to accomplish this through our control software with the help of a few fancy macros.  We are now able to utilize a single nozzle, heater and thermocouple which in turn reduce part count, failure points and overall costs.