Why Speed Pulls?

[Sousoulsu]

Now, let's look at the same scenario, 10 mobs, and see how RoT spam goes:
RoT potency=100. Ignoring the thing in common with the two methods (HT->RoT), let's look at how many RoTs you can do before you're at 200-250 TP.
14.
15670 potency on 10 targets with the RoT spam method.

It's clear that, being a skilled DRG, you will be able to tell when you should RoT (spread out mobs) or when you should Doom Spike(properly packed/LoS'd mobs by a competent speedrun tank).

RoT spam is not the way to go.
I do, however, think that a mix of RoT and DS is the best idea

all of the above about DRGs is, of course, irrelevant unless you need gear in that dungeon, because BRD BLM SMN and WHM are better AoE than a DRG. I just took the time to math it out to you to prove a point.