Currently we can import data into nearly any field through the import templates... this and 'Batch change' is a great way to update multiple items at once. However, there is no quick way to clear data fields in bulk... these would have to be done manually, one by one, and saving each item individually along the way.
Could we have a 'Batch Erase' option or even an import option whereby we import a unique phrase or wildcard that enables us to clear fields to blank.