In my opinion; This is only a real problem in one dungeon in my opinion.

Copperbell Mines Hard Mode

This dungeon is nearly impossible because the last boss is a complete DPS check and if you get sucked in by the worm once in the minimum gear, you wipe. DPS have to be on-point and the healer cannot slack, as well as take the crystals to the worm to ensure you do not wipe to running out of them. Had it happen to me on PLD a few weeks ago it was insane.