[Ginkasa]

The curse was that they would come and defend Gondor when they were called, not help defeat Sauron. It was also a one time thing. They just had to make up for their past cowardice and fight in another battle.

And if they thought that they would never be free of the curse. they may attack Aragorn for betraying them. They were about to when he first asked them to join him.

And the battle at the Black Gate was not actually necessary for victory, not the way you mean anyway. If Frodo and Sam were able to get to Mount Doom and destroy the Ring without needing a distraction, it would have ended without a battle. It was not a battle that was foreseen from the beginning of the war and one that they were trying to avoid I think.


*shrugs and walks away*