The only problem I have with this change is it being a DPS gain compared to Dark Arts. The skill would be used on cooldown and wouldn't be saved for its utility, making a fluff mitigation as opposed to an actual cooldown for Dark Knight. In my thread I suggested an 80 DoT for 15s, with a DA effect of a 10% damage down debuff for 15s. This would add choice to the skill and is still a DPS gain even burning half your MP. (500 total potency for 2400MP is a net 360 gain) and 500 potency + 10% damage down debuff for 4800MP is still a net 220 gain)
A link to my thread is here http://forum.square-enix.com/ffxiv/f.../357739?page=1
