Crappiest....Sit-rep...Ever. Tell me you didn't come up with this on your own.The strategic value of each battlefield is the same. Win any two and the war is won. You have already sent your troops. The other side uses no system of placing troops. Basically they are just as likely to send all of their troops to 1 battle field as they are to send 1/3 of their army to each battlefield. The question is asking you to evaluate how effective a 1/4:1/4:1/2 strategy is when your opponent uses no logical strategy. A tougher question could be, find the most effective strategy.
I was going to give it a shot, but how the hell do you develop a strategy or know where to send your greater forces w/o knowing the layout of enemy forces? Even if you don't know their strategy you should at least know where to concentrate forces. Methinks this problem wasn't developed by someone with experience in military history.
If you know the enemy and know yourself, you need not fear the result of a hundred battles. If you know yourself but not the enemy, for every victory gained you will also suffer a defeat. If you know neither the enemy nor yourself, you will succumb in every battle.
- Sun Tzu