Ok Pusaka.... you have sold me, that at the very least... you theory is worthy of further research.  After all gentlemen, it is a theory and as a theory, worthy of testing.  
 
 
Finding the earliest example of this style Greneng will give you an approximate "date" or date of influence.  While not an absolute "test," it may give a clue if it occurred before of after the Hindu influence.  
It may be a starting point.  
