To many variables to keep track of. The GM would be forced to pause the game each turn, recruit, tally the war weariness, reduce if necessary, check units to see if they desert (all involved in the war).
Mine simply requires forwarding each players prioritizations at the start of the term to the GM, who then recruits them, impartial to the current war. This is a once check thing, that does not require any tally checking beyond what we are already asking to be kept.
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