My initial calculations based on the Action Helps provided by GamerEscape suggest that skipping Blizzard IV may still be a damage gain in Endwalker. However, these calculations don't yet account for oGCD use, which ostensibly should have similar effects in either rotation but if lined up right may push the intended rotation back into the lead; Polyglot debt/surplus since one rotation is longer than 30s and one is shorter; and Firestarter opportunities provided by Astral Paradox in the intended rotation. So some more maths need to be done before we can draw any conclusions.
I probably won't bother until EW EA though, since potencies can still change in the next month. I just did this out of mild curiosity and an overabundance of time.
Surecast and Swiftcast were both always available to non-BLM magic users, though.
