Spent about 30 minutes really studying the Rebmrandt drawings and etchings in the following show (see below):

Rembrandt and His Circle: Drawings and Prints July 11, 2006–October 15, 2006 Robert Wood Johnson Jr. Gallery for Drawings and Prints, 2nd floor  

 From the Exhibition notes:

This exhibition celebrates the 400th anniversary of the birth of Rembrandt Harmensz. van Rijn (1606–1669). Selected from the Museum's world-class collection, these 58 graphic works by the great 17th-century Dutch master and his pupils illustrate the range of Rembrandt's creative genius—his spontaneity, originality, and innovative approach to traditional media.

What I noticed was how much Rembrandt's drawings are poetical - as a natural extension of himself.   I see many of the drawings as "pre-paintings" and while I don't go into the strong light/dark thing that was popular at the time - I do appreciate the poetry of his drawings. Sometimes, there's touches of pigment to promote depth - something I would not have thought that Rembrandt needed to do - since his drawings are so strong, as they are.  But then I realized, there really is not limitation on what an artist can or should do, save the limitations they put on themselves.   If Rembrandt need some pigment to pull out a face or a Tiger's mane, who I am say it's not the right thing to do?