Whilst I share your sentiments, to introduce this solely for the BLM would open up the proverbial can of worms. Healers then would also want this ability and so on.

With the exception of the Bard (which I will never understand why their skills are instant) all the caster classes are inducted. This has always been the trade-off in the majority of MMO's for ranged vs melee.

In no way am I telling you how to play your class but I guess in movement heavy fights you just have to better manage your rotation and skills (easier said than done of course).