That's good ideas - any known bugs?
Besides, that the AI has sure some problems, and the impact on performance, units can be "captured" on a plot, when one of your cities is captured/razed, or when a open borders agreement is cancelled.
Because of the code-optimation for the performance, there's a small chance, that you get a false negative answer. This means, that you cannot walk on a plot, but you should. This could only happen, when you have "strange" borders, because of a war in a very cultured area.
The first thing has to be changed, the second is only a minor thing, and it's needed for the performance.
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you mean, that a player shouldn't be able to move a unit, if he doesn't know, if he is in the radius of a unknown city?
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