And just exactly when were we supposed to do that? The WoW timeline does not follow any patch schedule or content release dates. We entered the Tomb of Sargeras, place the pillars there as we had to, and then we followed Kil'jaeden to Argus. Was the writing supposed to go something like this?
1 - "Hey, we've got to follow Kil'jaeden and finish him off!"
2 - "Wait, we need to take a moment and secure the Pillars of Creation! Sure Kil'jaeden can regroup and come back through the portal he just opened up in the basement of the tomb but at least the Pillars will be safe!"