For retribution paladins, you will have abilities with cooldowns that do not "sync" up. You will reach a point where you can no longer fit everything into a castsequence macro. Crusader strike has a 4 second cooldown, judgements are 8 seconds, divine storm is 10sec, and exorcism is 15 seconds. Even if you could write an unlimited castsequence, you can see right away that the cooldowns do not line up very well. This is where a click macro far outstrips a castsequence macro. You can basically simulate manually firing each ability when it's cooldown expires.
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