I've checked my PPS numbers for even the most optimal assumptions possible. Your expected PPS from a T1 cast if everything ticks for max duration is still about 10 PPS less than F4.

Quote Originally Posted by Garotte14 View Post
All the math seems fine, but you're missing something that no one has considered. The argument is, "If you get a fast umbral tick, is it worth it to cast Thunder?"

Well, if you are playing correctly, after you cast Blizzard III, you should have already qued your next cast. So technically, no matter which way you spin it, you should be casting Thunder or Blizzard. Otherwise, you are delaying a cast to see if you get a fast umbral tick. Delaying casting, even slightly will always be a DPS decrease.

The alternative would be to always que Blizzard IV after Blizzard III, but what if you don't get the tick? Casting Thunder at this point is risking Enochian and Fire IVs.
Let me elaborate on this line, and speak about the rotation in a vacuum while doing so:

Quote Originally Posted by Aloise View Post
The first condition, however, leads me to suggest a minor change in the rotation: Cast Blizzard 4 immediately after Blizzard 3, and Thunder 1 after that only if necessary. This will help reduce uncertainty about whether or not to cast T1.
Casting T1 after B4 has next to no adverse side effects on the rotation. There are exactly two situations in which refreshing Enochian becomes dodgy.

The first is if you refresh Enochian so it is now 20s, then cast T1. You get a T1 proc in the next 2 GCDs. In order to use that proc, you will have to position it before you finish all your F4s, which might lead to Eno falling off right before you finish the fourth F4.

The second is if you refresh Enochian so it is now 25s, then cast T1. You get a T3P during Astral Fire, and get a F3P as well. Your T3P will fall off before you cast B4. With some way to shave off a few fractions of a second (T3P > Swift F4 or Ley Lines), Eno will probably drop.

Outside of these two situations, casting T1 after B4 has no adverse effects on your rotation. This is, of course, in a vacuum. Outside of a vacuum, Swiftcast and Aetherial Manipulation exist, which help cut down on stress and lost time due to mechanics. There isn't a good way to objectively measure these things outside of the vacuum. But on a dummy, B3 > B4 > T1 is superior to B3 > T1 > B4.