Controlling data can be challenging. As an electric utility I have alot of requirements on data. An example would be street lights. I have 100+ options for lights and about 10 fields that need controlling, however, I have no desire to create 100+ subtypes since this would be tough to manage. Current we have only two subtypes in order to symbolize upon. As a way of controlling the large amount of optional data we propose a 'sub-subtype' or 'classifcation' (a second tier of data control). This way I can establish a series of classifications that control fields for each subtype without overwhelming the display and query functions that could occur with having too many subytpes.