Kramer is just CLASSIC as Dr. Van Nostrand in this episode. Notice when George wants to rush Kramer into the room to "examine" Kruger, how Kramer holds up his hand to slow things down while he assumes the Van Nostrand character (especially his facial expression). Then, when Kramer comes out of the room to speak with George, he holds the character for a few seconds until the door is closed and then reassumes the Kramer posture. Never fails to crack me up!