Playing from my hotel last night, raiding Al'ar.
Latency averaging around 1,500ms, peaking at 1,900, with one D/C right before a boss attempt.
The Al'ar fights would look like 1 second of 20 arrows flying from each hunter, 10 arcane missiles flying from the Mages, 10 bolts of what ever Warlocks do flying out of their hands. Followed by about 5 seconds of nothing. Just nothing.
Frozen in place. No movement. No firing. No potion drinking. No trinket activation. No Rapid Fire. No Bestial Wrath (poor Condoleezza, she was so sad, she needs a little BW lovin). Zero Drummers Drumin'.
Ended up gimping my normal DPS output by about 300-400.
During one Phase 2 attempt, the lag unfroze, and I was laying there dead. Stupid AoE flame hit, and I was lagged out and couldn't react.
Luckily, I fly home tonight.