Just keep in mind the CC builds immunities even on fodder. First use will likely go unresisted, second will be half duration, third will be 1/4th, and fourth may either reset to full or render the mob completely immune depending. As well, you'll have some mobs completely immune to things like sleep or bind, in part to likely teach tanks and healers how to handle multiple adds at once.
Anyway, THM/BLM is probably close to the spirit of the backline RDM some FFXIers loved. XIV's Convert is not XI's Convert, though, and Swiftcast is certainly superior to Spontaneity because of the recast difference. Lethargy is too restrictive on the recast to really be considered a reliable Slow, though, and the job has now Blind or Paralyze to flesh out the distinction.
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