I posted a stand alone thread for this, but I'll try this thread as well:
"I have a question regarding a specific timing of Dark Soul, with Afflictions 4 piece.
Before 4 piece, I'd normally just use Dark Soul at the same time as my Shard of Nothing on use haste trinket, lining them up for maximum effectiveness.
However, with the 4 piece, I have DS up more often than the flat 2 minute cooldown of the Shard. Should I be using Dark Soul as much as possible with 4 piece? Should I still hold it for the Shard use? Only use a Dark Soul with a RPPM trinket or 710 ring proc?
tl;dr What is the optimal Dark Soul usage with Affliction 4 piece?"