There are alot of circumstances in fight that normally decides whether or not its beneficial to go DWT early or not.
For Management purposes as well as other synergy like trickattack i personally tend to keep swiftcast, DWT, Aetherflow and tridisaster together, it locks your rotation but is way more easier to handle.
The other more dps-efficient way to handle it is to time your DWT so you can use Tri-disaster at the end of DWT together with deathflare.

In the end it doesn't really matter as long as you keep Aetherflow under CD, clipping dot here and there normally makes the small differences that ppl need to get used to in order to get to the very high percentages.