Let us evaluate how viable a destruction warlock is in heroic nightmare raids by using the available data/parses from warcraftlogs. Out of the top 200 warlock parses, how many of them are affliction, demonolgy, and destruction? Let us also shine some light on how the 5th best (dps wise) destruction warlock is competing with other damage dealer classes on each boss.
Skorpyron:
2017-01-20 heroic out of top 200 available wl parses: affli: 195, demo: 4, destro: 1
2017-01-28 heroic out of top 200 available wl parses: affli: , demo: , destro: 0
Chronomatic Anomaly:
2017-01-20 heroic out of top 200 available wl parses: affli: 107, demo: 80, destro: 13
2017-01-28 heroic out of top 200 available wl parses: affli: , demo: , destro: 25 ++ the 5th best destro is overall at position: 1226
2017-02-06 heroic out of top 200 available wl parses: affli: , demo:, destro: 19 ++ the 5th best destro is overall at position: 959
2017-02-16 heroic out of top 200 available wl parses: affli: , demo: , destro: ++ the 5th best destro is overall at position: 1383
Trilliax:
2017-01-20 heroic out of top 200 available wl parses: affli: 137, demo: 57, destro: 6
2017-01-28 heroic out of top 200 available wl parses: affli: , demo: , destro: 14 ++ the 5th best destro is overall at position: 2327 lol
2017-02-06 heroic out of top 200 available wl parses: affli: , demo: , destro: 8 ++ the 5th best destro is overall at position: 1915
2017-02-16 heroic out of top 200 available wl parses: affli: , demo: , destro: ++ the 5th best destro is overall at position: 2006
Spellblade Aluriel:
2017-01-20 heroic out of top 200 available wl parses: affli: 104, demo: 95, destro: 1
2017-01-28 heroic out of top 200 available wl parses: affli: , demo: , destro: 8
Krosus:
2017-01-20 heroic out of top 200 available wl parses: affli: 91, demo: 98, destro: 11
2017-01-28 heroic out of top 200 available wl parses: affli: , demo: , destro: 15 ++ the 5th best destro is overall at position: 2289
2017-02-06 heroic out of top 200 available wl parses: affli: , demo: , destro: 6++ the 5th best destro is overall at position: 2469
2017-02-16 heroic out of top 200 available wl parses: affli: , demo: , destro: ++ the 5th best destro is overall at position: 1962
Tichondrius:
2017-01-20 heroic out of top 200 available wl parses: affli: 140, demo: 35, destro: 5
2017-01-28 heroic out of top 200 available wl parses: affli: , demo: , destro: 12
2017-02-16 heroic out of top 200 available wl parses: affli: , demo: , destro: ++ the 5th best destro is overall at position: 4770 FOURTHOUSENDSEVENHUNDREDSEVENTY
Atraeus:
2017-01-20 heroic out of top 200 available wl parses: affli: 159, demo: 41, destro: 0 (zero)
Really? 0?
2017-01-28 heroic out of top 200 available wl parses: affli: , demo: , destro: 2 ++ the 5th best destro is overall at position: 1204
2017-02-06 heroic out of top 200 available wl parses: affli: , demo: , destro: 6++ the 5th best destro is overall at position: 830
Botanist:
2017-01-28 heroic out of top 200 available wl parses: affli: 51 , demo:66 , destro: 83 ++ the 5th best destro is overall at position: 552 (just wait till more shadows (90% of rankings) get to that boss)
Elisande:
2017-01-28 heroic out of top 200 available wl parses: affli: 10 , demo: 18 , destro: 172 ++ the 5th best destro is overall at position: 14
Gul'dan:
2017-01-28 heroic out of top 200 available wl parses: affli: 59 , demo: 69 , destro: 72 ++ the 5th best destro is overall at position: 358
2017-02-06 heroic out of top 200 available wl parses: affli: , demo: , destro: 67++ the 5th best destro is overall at position: 307
2017-02-16 heroic out of top 200 available wl parses: affli: , demo: , destro: ++ the 5th best destro is overall at position: 370
Keep in mind that there are still some awesome warlock players who play destruction. Just imagine what would happen to the statics if those few players would not be counted.
Conclusion: The data of the first three weeks of raiding in hc nighthold indicates that destruction warlock is total garbage in 7 out of 10 bossfights. It is a complete failure. The lack of adequate performance is hideous and can be easily backed up by numbers. However, in 1 of the 3 "last" bossfights (Elisande) destruction warlock is among the best speccs(frost DK, assa Rogue, Shadow). Only few % difference between those speccs. In the 2 remaining bossfights (Botanist and Gul'dan) destruction warlock is doing ok. At Botanist 6th position out of 24 dd speccs. Gul'dan 17th position out of 24 dd speccs. So in conclusion, if you play destruction warlock, you will be 7 * total garbage, 1 * among the better speccs, and 2 * in the mid of the pack.