Been going back through Barbarossa with some extra optional rules. What are the pros and cons of destroying factories in captured cities, can you turn those captured factories over to your production or is it better to destroy in case the enemy gets the city back they have to spend resources and engineer units to repair/rebuild?
Red factories can be used to produce for your own side, blue factories cannot. So it's usually better to destroy blue factories when they are captured, but not red ones.
Blue factories are usable to you, if in your home country or one of your aligned minors countries. So if you cease blue factories from the enemy you can destroy them so that it takes some time and bp for him until he can reuse them, should he regain control of the hex. There is also an option requiring Eng in the hex in addition to the time and cost.