I think the John Earman and John D. Norton argument pretty much ends the discussion. What they are saying is that the allowing the demon to violate the second law of thermodynamics boils down to a violation of the second law of thermodynamics - thus circular reasoning.
But it brings you back to the point of what drives the second law to begin with - just statistics. A violation of the second law of thermodynamics isn't impossible, just unlikely. If Maxwell's demon opened the door and a hot molecule just happened to cross from the cold side to the hot side, he could declare a win - based only on luck.
We live in a special case universe where there is ever increasing entropy and thus a direction to time - owing only to the fact that we started with a very low entropy condition just 14 billion years ago. If the universe ever settles into a warm death, there will be no increase in entropy, no second law, no direction to time, and no remaining evidence of an original Big Bang.
And to quote .Scott's post "If Maxwell's demon opened the door......" always a first action needed.
The thought I use is... An air compressor installed inside an air tank which is designed to operate as an air motor(turning the compressor inside), air being drawn in through the axle tube into the compressor and discharged into the tank, after a period of time the tank is under pressure and hot, the hot air is expanded through the tanks motor function and at zero pressure and lower than intake temperature, the air moves back into the surroundings.
The compressor is equal to the demon, it should boil down to a time, temperature ratio of work performed.
What is considered useful will determine if it has value IMO.