Grassley and his committee (don’t forget, every Republican member of the Judiciary Committee signed the letter) are saying that they consider their advice to Barack Obama to be not to submit a nominee, and they will act in accordance with that advice by withholding their consent.
What’s the point of holding hearings on a nominee that will never be confirmed? Politics, pure and simple. The Senate is within its rights not to play that game.
The duty is to advise and consent, not to consider and rubber-stamp.