I've gotten to Titan... and experienced the lag. Worse, I have seen other players completely out of the highlighted area, get hit by landslide. It happens in other fights before Titan...but Titan is the first fight where not dodging is an instakill.

Square Enix, the lag between the game firing off an area attack, and the game rendering it on the screen has not 'taken care of itself'. If you can't fix it, this game isn't going to have much of a lifespan. The majority of players have now arrived upon the Titan fight, and I imagine all fights going forward have the same one hit kills, people are going to get sick of the lag real quick. Fix it for your own sake.