Did the devs lie to us? Either actually make BLU OP, or unlock it

[Seraphor]

While BLU definitely needs some balancing tweaks, and increased potencies is at the top of that list, the job isn't OP because of potencies, it's OP because of mechanics and gimmicks.
An OP healing spell, vast damage and defense buffs that are no competition for the other jobs, and a bucket-load of enemy exclusive debuffs that are not available to any other jobs specifically due to balance.
They'd never give a regular DOW/M the ability to paralyze, or petrify.

It's potencies actually aren't that horrendous compared to other level 50 DOW/Ms that are geared to that level (ilvl 90 or so), considering it gets a 50% Maim and Mend compared to other jobs 30%, and it has the ability to increase it's own potencies by 50% and decrease enemy defence by 80%! This effectively translates a 130 potency magic attack into something more comparable to effective 350 potency, which is on par with an AF Fire I.

There's definitely room to grow, it should be able to match a regular dps spell as a general attack, rather than only reaching it with all burst modifiers in place, so yeah the potencies are a bit lackluster, but it's not horrendous and I hope the job will get these sort of tweaks down the road.
It could also do with about a 50% HP buff too.