Well, first of all, administrative points are better spent on coring provinces than on developing them, second, administrative development is related to the tax base, which only gives you tax income which doesn't have many modifiers that help it grow, while, on the other hand, diplomatic development is tied to the goods production, which is also directly related to the trade income, the amount of modifiers that can influence both of those income sources is very big and increases progressively all over the game, which means that a well developed nation can easily have most of its income coming from production and trade. This can be achieved through the right combination of ideas, policies, buildings, privileges and other modifiers, some of which are temporary, the key is then to exploit a time window on which dev cost is reduced to its minimal expression, while you have a surplus of power points, specially diplomatic and military points… “why diplomatic and military?” you may ask… The Dev Cost Meta, briefly explained, consists on stacking various modifiers that reduce the development cost of provinces, with the objective of facilitating higher levels of income and manpower base, since both values are closely tied to the development of every province comprising a nation. The answer to this question comes in the form of a particular technique known as the “Dev Cost Meta”. Yet almost every player has come up to a point where they wonder: “How can some players get those incredibly strong nations?” A question that becomes even louder once the top tier competitive MP games are discovered, where nations comprising sometimes not even more than 4-5 regions in Europe are capable of fielding hundreds of thousands of soldiers and have millions of reserve manpower, all while keeping a healthy balance. (Image form my Mewar > Rajputana > Bharat run) India can be a nice land to conquer, but it's also excellent to dev.

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