Any use for military governor building line?

[Fisherking]

There are some regions that are never able to build more than the palace line. In those regions the military governors allow you to build more troops and have two builds for units per turn. It is better than never being able to build more than a single militia per turn, though it has a slight negative impact on economics and region suppression.

[MikeV]

There are some regions that are never able to build more than the palace line. In those regions the military governors allow you to build more troops and have two builds for units per turn. It is better than never being able to build more than a single militia per turn, though it has a slight negative impact on economics and region suppression.

Which regions limit us to only one line, and why?