Appreciate the responses!

I was attempting to help speed up data entry for my users by allowing them to select a small range of cells in an unstructured area and simply dragging them over to input fields where the formulas do their thing (data validation).

Its probably almost just as quick to do a Ctrl+C and Ctrl+V but since they will be doing this multiple times, thought it would be nice to allow simple drag and drop. In researching this, appears to be an Excel limitation.