Quote Originally Posted by CKNovel View Post
They can sustain themselves.
Dark Knight & 3 DPS run exists, here's one where the Dark Knight doesn't even cast Dark Missionary once and keep Oblation/TBN to themselves. Here's another one for the second Expert dungeon and finally Alexandria where the DRK press slightly more buttons.
This DRK at the end of last pull before the first boss is down to 20% HP. This isn't sustain, this is mitigating and absorbing enough damage to survive before the trash dies. Doing a speed run of a dungeon in savage gear is not indicative of normal play, and ironically replacing one of the DPS with a healer in this run would vastly increase the odds of DRK needing some healing due to the DPS drop.

If you do a random roulette, and you get players that are not geared or just not very good at pumping out DPS, DRK will need healing period. Compare that to a WAR who can go into the same dungeon by themselves, w2w pull and clear the whole thing alone without any help.