Th...then don't use your Firestarter and Thundercloud procs when you don't have to move? Instead continue to cast Fire 4 and Fire 1 to refresh Eno and Astral Fire stacks, as you should be doing, and when you have to move, use that instant Fire 3 or Thunder 3 you have waiting in the wings so you can deal some damage when you move? Or Triplecast to cast Fire 4/1 on the run? Black Mage is the hardest class to optimize just because movement is their arch-nemesis, but it's really not that hard to understand why instant-casts are integral to your kit.