Quote Originally Posted by Lilyth View Post
A GCD is a GCD?
While two fire IIs take 6 seconds to cast (not taking into acount SS), a Thunder plus a TC proc only takes 5.
That's the heart of the issue, a GCD isn't the main factor in BLM Flare AoE. Your 2 GCD casts of 2.2 seconds each doesn't add 4.4 seconds to the rotation, it adds 6.0 seconds. Your rotation doesn't change from 15 seconds to 19.4 seconds, it becomes 21 seconds due to server side 3 second MP ticks.

Quote Originally Posted by Lilyth View Post
(this is particularly fun to do when a known tank is still moving forward pulling mobs so you can keep moving with him and casting TC procs instead of scathes)
That is part of the pull, not part of the AoE rotation. Thundercloud works during the pull, at the start of a rotation to weave in RS/QS, and sometimes after that first Flare > Transpose while waiting on the first MP tick. After that first Transpose > Fire 3 it's a dps loss.