Are you claiming that Yudkowsky is a transhuman AI?
Of course not - but dismissing Yudkowsky's victories because the gatekeepers were "thinking poorly" makes no sense.
Because any advantages Yudkowsky had over the gatekeepers (such as more time and mental effort spent thinking about his strategy, plus any intellectual advantages he has) that he exploited to make the gatekeepers "think poorly", pales into insignificance to the advantages a transhuman AI would have.
Update 2013-09-05.
I have since played two more AI box experiments after this one, winning both.
Update 2013-12-30:
I have lost two more AI box experiments, and won two more. Current Record is 3 Wins, 3 Losses.