Infraction: 1. All posters are to make an effort to communicate clearly.
Message to User:
The first person pronoun, I, should always be capitalized.
The set does not increase the damage of Death Strike in any way, since DS's damage itself has no disease modifiers. It's part of the reason why 4pc t8 seems so bad compared to using pieces that are superior statwise.
Woops, my bad. Haha, didn't think of that.
Anyway, i don't think that the increase to Obliterate are big enough for you to change to using Obliterate over Death Strike, which i think you wanted to know by asking your question.
Please do correct me if i'm wrong in this assumption.