So I am told over and over that I am doing things wrong as Black Mage, but based on my understanding on how things work my way actually works better.
Other people: Fire III, Fire IV x2, Triple Cast, Fire IV x2, Despair, Blizzard III, Blizzard IV, Thunder III, repeat
10 spells
Fire boosted potency: 310, 310, 310, 310, 340 = 1,580*1.2*1.3*1.8 = 4,437
Other potency: 260 (first Fire III not boosted), 260, 310 = 830*1.2*1.3 = 1,295
5,732 effective potency per rotation
Me: Fire III, Fire IV x2, Fire III, Fire IV x3, Despair, Transpose, Xenoglossy(otherwise Blizzard IV if no Polyglot and late tick on mana), Blizzard IV, Thunder III, repeat
11 spells
Fire boosted potency: 310, 310, 260, 310, 310, 310, 340 = 2,150*1.2*1.3*1.8 = 6,037
Other potency: 260 (first Fire III not boosted), 310, 310 = 880*1.2*1.3 = 1,373
7,410 effective potency per rotation
(1.2*=enochian, 1.3*=maim and mend, 1.8*=astral fire boost)
Granted spell speed can play a factor. If you have enough spell speed you might be able to get a fifth fire IV in which would put total fire damage up to 1,890 vs and match my 11 spells. Even then it is still 1890 vs 2150 and you would have to build spell speed vs critical hit/determination/direct hit. Also other people's combo requires using Triple Cast to get everything off in time or remove a Fire IV. Mine has 7-8 seconds after first Fire IVs are done so you can move/interrupt if you need to and save Triple Cast for when you need it. Also when do you use Xenoglossy in most people's rotations? Xenoglossy isn't fire damage so it doesn't get the 80% boost from Astral Fire... so why cast it in your fire rotation?
Also I know most people don't use Transpose, but 1 Umbral Ice is enough to fill my MP over 3 casts (Xenoglossy, Blizzard IV, Thunder III usually) so I don't need Umbral Ice 3 (This is why I skip Blizzard III). Transpose is better in my opinion since it isn't on global cooldown. You can start casting right away after using it. You might say "But if you just did Despair you don't have the MP for Blizzard III". You are right... but it also depends on when your MP ticks. If it ticks right after you transpose you can get it off right away. If not I also usually have a Xenoglossy I can use which doesn't cost MP. There is some thinking in the situation involved.
Side note... why I do not Fire IV 3 times after the first Fire III. You are trying to have your second Fire III hit the last Umbral Heart. This way you are at 1600 mp when you use Despair the last time. Otherwise it would be Fire III, Fire IV x3, Fire III, Fire IV, Despair without Fire III's 2k discounted mana from Umbral Heart.
Also I know you can Manafont after Despair to get another Fire IV and Despair in afterwards, but you can do that regardless of the combo. With Manafont being on a 2 minute cooldown you can't do this every time as well.