Complex Math Question

[Sarcatica]

Using Unchained means you lose 3rd FC's 500pot + 5% Deliverance + Maim + Storm's Eye + Berserk VS -20% damage for 1 full combo of Power Slash (slashing debuff not up too) + Low Blow + Dark Passenger + Unmend at start. This is what I can think of. Let me know if there is a loophole. Has anyone tested how offensive buffs work? Flat or multiplicative? Let's just assume flat boost for now. Slashing debuff less than 10% effectiveness? In terms of what WAR and DRK lose and gain with different roles is as follow.

WAR OT, DRK MT:
DRK: No slash debuff, Grit on. 150 (Unmend) +150+220+300 (PS combo) +100 (LB) + 150 (DP) = 970pot. Simplying things, let's say it's a flat -20% in Grit. 100% (Darkside still up) x 970pot = 970pot.
WAR: Gain 3rd FC in 1 Berserk. Simplify things and make it a flat boost, 500pot x (100%+5%+20%+10%+50%). 500pot x 185% = 925pot.

WAR MT, DRK OT:
WAR: Loss of 3rd FC, Loss of 5% from no Deliverance + slash debuff at start for 1 Tomahawk+ Brutal Swing + BB combo (assuming if NIN puts up slashing debuff for WAR) = 150 (Tomahawk) + 150+200+280 (BB combo) + 100 (Brutal Swing) = 880pot
DRK: can do DASE combo more with Darkside up and slash debuff up (150+250+400) x (100%+20%+10%) = 1040pot

Admittedly I have no idea how offensive buffs work exactly. Again, let me know what I am missing or feel free to correct anything here.