When you play in the raid zones, you must deal with the Bulwark script, especially for fighters. I sometimes get lag spikes when this orange message script triggers, so I missed to counter Bulwark of Order that makes group members get more damage. I wonder if some other players have experienced this kind of deadly lag.
It might not be lag. There is a bug with Bulwark.. while you can cast it while you're casting another ability, if the other ability finishes before bulwark does, the first ability triggers global recovering speed... and cancels Bulwark.
Everyone in my raid group have experienced lag spikes before that orange message shows so I don't think that kind of problem.