Define optimal. Are you optimizing for:
A. Most possible segments
-Dozens of setups are optimal.
B. Most possible segments with lowest average clear time
-Good case for WARx3, but can you show that a third warcry helps more than jig would in a setup like DNC WAR WAR? You're assuming because the current most accepted setup is WARx3 that it's the best, but you don't have any evidence.
C. Most possible segments with lowest chance of death
-DNC definitely better than WAR.
D. Most fun
-Depends on player.
E. Most acceptance from shout groups?
-Definitely gonna go for WARx3 here, hard to change minds.
...The argument on Kalunga seems a whole lot easier. 10% JA haste for everyone who is engaged besides the DPS is vastly more extra damage than any difference between WAR and DNC. Having an instant aoe cure is a huge safety net. 23% more defense down is an insane amount of extra ratio and will make aria useful.
Edit: I have to think some of the vitriol in these threads is coming from the inherent FOMO of having to choose a weapon. It's ok not to pick Onion Sword III; there aren't going to be enough top tier DNCs that shouts only demand onion sword DNC. Your WAR is still going to be desired even if DNC finds a place alongside it. Same goes for Kalunga. If you don't like DNC, you don't need to pick it.