Option to halve GCD time and double potency in non-synced/instanced content

[catofsnake]

if you do this without also doubling cast times, then you basically give BLM similar movement to dualcast with no penalty in damage. Obviously not a good idea. Like, you want your GCD to be 5 but your cast times to be like 2.8 that's basically a GCD of free movement for every spell.

...Why would you assume a concept like this wouldn't include cast times? And even if it didn't, do you really care? I thought by stating that this would only be for overworld content/not baldesion arsenal, no one would have any stake in something like this being added. And, for the potentially most unengaging/repetitive content in the game, at that.