Best rotation is purely through corruption (with all applicable aff talents) up on every mob you're fighting in a pull and then SB spam each mob in kill order. None will last long enough for a full aff rotation and corruption shouildn't tick for enough to pull agro away from an ae tank on the mobs not being actively tanked.

It's a slight cheat but it's the way we have to work and you should see your total dps in the run improve significantly.

For boss fights it's simple....use all your dots and sb spam until you need to redo them with tapping in between. You will need to sit down with a spreadsheet and play around with each dot and it's number of ticks to work out the best order for you of applying them so they all run out around the same time (so you can keep as much uptime as possible) but it's fun to do as it's a real mental challenge.