To clear some things up.
Dual wield DOES indeed add the two wielded weapons delay together. However, it also gives a slight delay decrease (10%) at lv 10.
This would mean, Wakizashi, Dmg 7, dly 227, dual wielded would end up something like this: Waki227+waki227 = dual waki 454 x 0.90 (or /100x90)
This means 10% of 454 is removed from the delay, = 45. So the dual delay is 409.
This does increase DoT fairly significantly, even at lower levels, because you would be swinging 11 times total while dual wielding, compared to 10 times total when single wielding in around 20-23 seconds.
Lv 25 DW is the same, but 15% decrease.
Lv 45 DW again the same, bu 25% decrease.
Lv 65(?) DW provides a 30% delay decrease. This would decrease dual wakizashi's delay about 135, bringing the delay to 319, allowing the NIN to do about 50% more DoT.
Also, to answer the questions about usage as main vs sub, dual wield does apply from a /NIN as fully as a main job NIN of the same level. However, as subjob level cannot exceed 37, only tiers 1 and 2 (10% and 15% delay) are available, and not the greater boosts to attack speed. While this makes dual wielding swords, axes, daggers, clubs and other one handed weapons perfectly viable, the tier 1 (10% reduction) DW doesnt give an improvement in many cases to 2H weapons available. For example, a WAR lv 20. Two ideal options would be:
Great axe: Neckchopper, 39dmg, 489dly and +5acc.
Dual wield swords: Auriga Xiphos, 17dmg, 224dly, +2acc
And: Degen+1, 15dmg, 218dly.
(I use neckchopper for this example as i personally see greataxe as the..'traditional' WAR weapon, and im not alone)
Great axe total = 39dmg, 489dly and +5acc. Dps = 7.97546.
Sword total = 32dmg, 403dlg and +2acc. Dps = 7.940447.
Although a difference of 0.035013 dps doesnt seem like much, over 100 strikes with a great axe, over 8.15 minutes, the great axe would do about 3/4 dmg more than DW swords. This is assuming a lv 20 WAR even bothers getting the Auriga Xiphos, which adds just under 2dps to the DW.
Whatever way you look at it, greataxe has a slight advantage at this level.
However, at level 50, WAR/NIN gains access to DWII, a 15% delay reduction on swords.
For example:
Great axe
Leucous Voulge +1, 80dmg, 489dly.
DW swords
Tactician Magician's Espadon x2. 38dmg, 257dly, +12 attack.
Totals:
Leucous Voulge+1 = 80dmg, 489dly = 16.359918 dps.
Tactical Magician's Espadon (x2) = 76dmg, 437dly = 17.391304 dps.
While still a fan of greataxe, for pure DD capabilities, DW now is a viable choice (especially when you consider the whopping +24 Attack from weapons alone, +40 and +4 original dmg, -32 base dly with T.M. Espadon+2).
As a rule, if Sword is capped, fine, if its more than 5-10 at most off cap, either cap it or stick to greataxe.
Sadly this is as far as a /NIN job can get, as the next tier of DW is at lv 45.
Saying this, lv 45 is where the REAL fun starts with NIN/XXX jobs.
Having leveled NIN to 75, i have tried out some different combos with DW.
NIN/THF for example - 65NIN/32THF. DW-IV, SATA.
Dualing Kogitsunemaru, 34dmg, 227dly (also drains vermin...rarely a useful trait), with Sairen, 31dmg, 238dly, +3str and +7 more str on darkday.
Total = Dmg 65, Dly 325.5 (326). Dps is about 20 base.
With SATA combo from lv 30+ THF subbed, i personally hit 300s relatively often on IC mobs, higher still on VT or lower mobs. Your tank not keeping hate enough? HE IS NOW!
And my personal favourite: DW DAGGERS! XD
Highest DD damage is two mighty knives on winds day.
Total 66dmg per, at 200dly, +1 agi and +1 chr.
Ends up DW as 132dmg, +2 agi, +2 chr, 280dly. Dps = 47.1!
As this effect is...tempremental at best, another combination i find almost as good (and much, much more reliable).
Heart Snatcher, 15dmg, 205 dly. When the latent is broken off, 45dmg, 205dly and +6% crit.
Dualed with
Blau Dolch, 28dmg, 178dly. By keeping TP below 100% and using WS's as soon as you hit 100%, the latent and hidden latent effects remain active constantly, resulting in 59dmg, 178dly, Acc+5 and attack+16.
While time consuming to break heart snatcher in, and limiting on SC's in keeping TP below 100%...consider all those shark bites.
Totals:
104dmg, +5acc, +16 atack, +6% crit, 261dly. Dps = 39.9/40.0.
And the stat bonus's as well.
Either way, combined with SATA and/or sharks bite, this becomes more efficient than stonesplitter polearm, even with penta-thrust.
Either of these dag combos can throw out 500+dmg on IC mobs. yeh, this isnt as much as some sword WS or SCs, but gods, thts 500+dmg worth of hate extra on your tank.
As a last note...viper bite would be lovely but needs THF main..thus forbidding DW III and IV. Saying that, shark bite and dancing edge are superb multi-hit pure dmg WS's for a NIN.
Erm..yeh...sorry, this was more of a rant about my love of DW than anything. Oh well, hope u enjoyed XD
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NIN 75, THF 75, MNK 75, SAM 49, RDM 47, DNC 47, DRK 37, WAR 37, SMN 37, WHM 37, BLM 37, RNG 14, SCH 11, BLU 11, PLD 10, BST 10, PUP 4, BRD 1.
Fishing 87
Cooking 34
All others. 0.
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