I sub DRG pretty often.
FYI: So far those sub still has a use:
Standard SJ:
/WAR: SAM RNG BLU DNC THF PUP COR
/SAM: RUN WAR DRK DRG
/RUN: Any melee doing delve
/NIN: RUN, and any melee doing higher BC
/DNC: Solo, dyna, BST and COR
/DRG: COR or none relic RNG
/BLU: PLD and RUN
/WHM: BRD, GEO or solo RUN
/SCH: RDM, WHM
/BLM: SCH, RDM, GEO mostly for stun
/RDM: BLM, GEO, WHM
/RNG: COR when racc is needed
12 SJ out of 22 jobs are often used in events.
SJ that's rarely used or extremely situational:
/THF: For flee moving in town or TH solo.
/SMN: When you need a pet to split dmg.
/BST: BLU spell hunt....if you're still learning spell
/DRK: Alternative SJ for stun
/BRD: for movement speed+
/COR: Solo EXP/CP maybe?
So that's 6 extra SJ that could have a use in rare situations.
SJ I can't think of a use at all:
/MNK: Ppl used to use it in abyssea, not anymore.
/GEO: Can't think of a use
/PLD: Can't think of a use as well
/PUP: Looks cute and that's it
Seems only 4 SJ are completely useless, 6 are rarely used, 12 are used fairly often.