Can someone give me an in-depth explanation why Summoner is arguably the worst DPS?

[VanilleFang]

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This would be good for SMNs but it would make it so SCHs would have basically infinite MP. Besides, I like my slow. ]:

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I doubt it. Every point of Piety gives every class/job the same amount of MP (8 at level 50), they won't adjust it just for one job. Or at least I highly doubt they will.