Issues with Titan Normal and Lag

Seriously, I had a decent group from pug yesterday. I am a 35 pally with around 1700 hps over 360 defense and understand how to use and loose aggro. My group from duty finder seemed to be decently armored as well.

For all of us this was our first time with this mob. We learned quickly that titan wasn't as bad as we thought but we got him to within a sliver of health 5 or 6 times.

Our main issue was lag spiking, for all members. I would see the healer, who was very good and attentive suddenly be caught in a one of the direction attacks that Titan did when I know she was trying to move to a safe spot. Even as her character moved out of the directional slot her client would not update and she would be killed.

Why is lag such an issue in such a small instance? I sent a bug report but don't think it will be considered seriously. Anyone else have this issue?