Is this the star block?
http://youtu.be/6fA0-P4RDu4
More or less. I actually teach the first part with the single blocks first as Blocking Set 1, and then the full part with the single blocks the double blocks and the opposite sides (right out/left down, right in/left chamber, etc) as Blocking Set 2. He was struggling with the first 5 basic blocks in the air.
I think a big part of that was that his second black belt was in a certain kicking style that de-emphasizes blocking and striking with the hands. I can't say how legitimate his rank was in that style, I never really knew and it's been a long long time, but it seemed like the idea of using his hands was pretty foreign to him. Oh well. I hope he went on to better things.
-Rob