This was originally suggested/requested in the forums:
http://forum.compass-project.org/thread.jspa?messageID=293776
The Compass user should be given the option to provide a list of fields that will be used to create the dictionary. Non-text fields (i.e. boolean or date fields) do not make a beneficial contribution to the dictionary and indexing them is generally a waste of time.
I included "Compass GPS" and "Compass Spring" as affected components since I imagine the implementation will touch these two components.