Originally Posted by
Hontaro
Also, with a certain PIE threshold and under certain conditions, the basic BLM rotation changes to AF3 -> Fire IV x2 -> Fire1 -> Fire IV x3 -> UB3, which means that you can use a third Fire IV at the end while still having enough mana and time to switch to UB3. With your "movement" rotation, you will lose out on 2 Fire IVs in this case, which is an even more severe DPS loss.
Another thing I want to point out is that yes, it is possible to "F1 > Scathe > F4 twice", but only if Scathe is cast directly after F1, which means that if you have to cancel mid-cast and use Scathe afterwards, the duration of AF3 will not be enough.