The Turing Test is a bit like a driving test, it represents a demonstration of performance capacity of a particular set of behaviours under a certain set of circumstances.
Just because the 17 year old version of you was presented with a license to drive, doesn't mean that you didn't crash your parents car into a lamppost 2 weeks later.
The test is inherently subjective*.
Jaron Lanier points out in his Agents of Alienation essay that one reason that a human judge could not distinguish between the computer and the human, is that the human (as an individual, or humanity as a whole) might in that instance no longer have the ability to demonstrate or judge intelligent behaviour.
One only needs to peruse the comments made on a youtube video to accept the possibility that humanity is walking back down the hill of the fitness-landscape of intelligence. So touché Jaron.
Given that observation, humanity generally doesn't select its elites from the pool of frequent youtube comment makers, nor do we select our Olympic athletes from the range of characters in my local pub at closing time on a Monday night.
In the classic chess battle of Man Vs. Machine humanity didn't just field a good player, we fielded arguably the greatest human chess player that has ever lived.
So given the assumption that we could field high quality human players for judge and opponent, would they be motivated? If there was money involved I think they would be.
I am willing to bet real money, that I* (as the human player) could always beat an AI opponent that didn't have a model of the shared-reality grounding of the two human participants.
Pretty much like every test in psychology is subjective (unless you MRI the test subject or something)
Jaron Lanier, Agents of Alienation (Part 2)
Jaron Lanier has crazy cool dreads.