The question I have is: What was the GRA's motivation?
One colleague on a list suggested it was spiritual. IE The GRA wanted to soak up the Q'dushah like a sponge. Another colleague suggested it was educational. Instead of hearing [sometimes disputed] accounts re: the Avodah and the Middoth of the Keilim, he wanted to see it for himself how Seder Kodoshim worked in person.
What do YOU think?