If superior forces are what matters then why'd America lose in Vietnam? Common sense tells me it's a combination of many factors varying from scenario to scenario that determines the outcomes of wars.
In the Marrocidenian War's case I'd predict a stalemate. Terran is unable to mount an offensive by itself and I'd reckon that most of her allies couldn't sustain a campaign far enough South to hit Aurvandil's core. Aurvandil for it's part can only raid the Southern portions of Terran due to logistics and the fact that there are a couple of fortesses blocking off the Northern 2/3rds.
Victories in this war matter insofar as that it's fun to win battles and unfun to lose them.
