Here is a crude table (and I do mean crude)

https://docs.google.com/spreadsheets...it?usp=sharing

First table is using the AoE combo to refresh Surging Tempest every time, second is using all single target. This take into account direct crits and the fact you do not start the fight under Surging Tempest, keeps track of Beast Gauge and the timer for Surging Tempest, always refreshing before it runs out and the timer for Infuriate.

Since this is just a messy mockup, it isn't intended to be pretty, but hopefully the info needed is there. This runs for 2 minutes and you can see 2 columns for damage, one is just the potency for the attack and the second is the running total potency up to that point. As you can see, the AoE combo does pull ahead to start with, but that is only because it can initiate the burst 1 GCD sooner, after that, single target will win, single target also ends with more Surging Tempest and Beast Gauge.

Since this was put together relatively quickly I do not expect it to me mistake free, however, it should be a good enough indicator to show that the AoE combo is not good for refreshing Surging Tempest in single target.