Were your duty support NPCs DPSing the nail? The one I witnessed was not.

If a newbie fails twice that is enough of an issue to say that others may have the similar issue. Remember we have to think about this from the context of a solo player who this is their first MMO experience who doesn't know their rotation, and isn't synced down with high level gear as a black mage with a maximum stat weapon. Weapon damage is stronger than you realize, so they might only have a level 15 weapon.