As someone who actually plays Black Mage and is currently in T8 let me make a few things clear. Black Mage has the LOWEST single target damage out of all the dps classes even when NOT moving. If you had the best player of each class and allowed the black mage to stand still the entire time they would still be last place in dps.

However, I realize that there will always be a last place I just think it shouldn't be the black mage class as we have the lowest damage and the lowest amount of utility. Our class is only good for damage and yet it has the worst damage it doesn't even make any sense. Movement isn't the biggest issue as skill can compensate for this. Yes, we have good aoe, but that isn't very useful for high level raiding. In my opinion our THEORETICAL single target damage should be around that of a summoner. Currently Summoners have better utility, less penalty while moving, and much greater damage please give people a reason to use the "other" caster class.