I'll preface by saying I don't want war nerfed. I think though the slashing debuff is a source of problems. It leads to the disparity in parses, but war is the only class that can apply it permanently and it synergizes with nin and all other tanks. Since you have to select 2 out of the 3 tanks, this slashing debuff, combine with nearly infinite tp means war is almost required in all 8 man parties. At a minimum slashing debuff is affect 2 members of the party, and just get better with each nin. I do think it would help if they allowed nin to permanently apply slashing debuff.