This is actually a tough one.
I do believe that there are circumstances when it is appropriate for an official to assume greater responsibility, and war is one of those times. However, giving the President the power to essentially take over an office leaves someone without a job, and in an in-your-face kind of way. It also gives one person more power than may be prudent.
It would be better to have the official run the deparment, and have a mechanism for remedy of the situation if and only if results are inconsistent with the overall plan.
DZ is right in a way, we need some conflict to make the game interesting. Many of the most memorable DG events have been incidents where someone wasn't going along.
I'm going to hold off a bit and see what other comments may arise.
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For an example (extraterrestrial but still interesting) of changing official roles based on situation, look at the book Footfall by Larry Niven and Jerry Pournelle. The fithp herdmaster essentially gives up control of the ship to the attackmaster while on the offensive, and to the defensemaster when threatened. If we followed an analogous system in the Demogame, the military advisor would be two roles for attack and defense, and one or the other would take over for the President during times of war.
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