So while the Frosworm (in fact Ulfric′s actions led to the Frosworn creation) still plaguing the land, the Stormcloacks are fighting the Empire. So as result, BOTH , the Empire and the Stormcloacks (thus means, the forces in Skyrim) are weakened, severely.
Guess who is the only one benefited from this? Yes, the Dominion.
I guess they are laughing as they see their enemies destroying each other.
The excuse of the Gold Concordant is absurde, the Empire accepted it just to stop the bloodshed, and that is how Ulfric pay it: shedding more blood, and benefitting the Dominion!!
And he even dont care in kill his own people. Not a good king, not even a mediocre one
So for me, Ulfric is a horrible strategist, and a murderer.
