I am not sure if this holds true for all casted spells, however here is my experience from tonight.
I'm using a Hierophant's Crook, which has an Earthquake proc on it. It procs perfectly fine, with no issues. However, if I get a proc from my staff, and then attempt to cast my mem'd Earthquake spell - I get an error saying recast time has not been met. My guess is that the staff proc is somehow triggering the cooldown on my spell cast.
I honestly do not know if this was a classic "feature". However, I do know that it seems stupid, and figured I'd make a post
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