How does Mercentailism work?

[warbean]

According to its description, Mercantilism adds 1 free specialist per city. How exactly does this work? When I click on my cities, some of them have specialists that clearly say "Free Specialist" while others are completely unchanged.

Is there a pseudo ectra population added to each city that can only be assigned to a specialist slot or am I missing the point entirely? The whole civic seems to be slightly bugged at the moment - anyone fooled around with it so far?

 

[Khaim]

Well if one of your cities had a specialist before, then that may be your free specialist and you have an extra worker in the field.

They're not really an extra population- they don't count towards city size, don't eat food, etc. But they give the effects of whatever specialist they are. Very useful, since at worst they give an extra hammer.