It's really unlikely that you'll end up needing it unless your DPS are literally letting their cat walk all over the keyboard since one failed meteor sphere is survivable even with no mitigation at all and you'd have to let the limit break build really far for the Scholar to need extra mitigation, but it is an option other than making more DPS. Even with competent DPS, ignoring one comet could let you use cooldowns elsewhere and it's probably a totally good strategy to do with or without a Paladin and/or Scholar.
It's not only undesirable for DRK, it's also undesirable in my opinion since at least one and probably two of these particular mechanics can't be mitigated by the majority of utility skills as far as I can tell (Virus, Dragon Kick/Delirium, Storm's Path, Disable). It's fine to have a few mechanics like this in a fight (they've always had them when primals jump and stuff), but it's no way to "fix" a job.