The Definitive Dark Knight Guide

[Xenosan]

Ignore MP cost. For comparison you should assume both rotations are using the same amount of Syphons, Blood Weapons, and Blood Prices. \

All that matters is the differential. Which is sacrificing +350 potency for +0.5 the cost of a Dark Arts.

Souleater is 260 potency, DA'd Souleater is 400 (+140) - not sure where you're getting 150 and 160.

C&S is 100 potency, DA'd C&S is 450 (+350) - not sure where you're getting 150+300.

Like Malusion said last page - you can't compare 400 (DA'd Souleater) to 450 (DA'd C&S) - because C&S is oGCD and doesn't disrupt combos, it's benefiting from unbuffed Souleater - if the rotations are identical:

C&S buffed is 450 + 260 (Souleater) = 710

Souleater buffed is 400 + 100 (C&S) = 500

It'll take 2 C&S before a 'free' +140 is available to the unbuffed C&S combo, which is not as good as +210 from constant C&S buffing.

The ratio is constant. It doesn't matter how long the encounter - not buffing C&S will never amount to higher DPS unless it's an AoE situation.