I'm sure there are a lot of people that just screw it up terribly, because they are either new to the style, are very young, lazy, or just not capable. but I'm not one of those people, I always do my research and I practice with damage calculators to verify rotations and could probably write strategy guides on this game with a lot of boring work. I just need to punch in numbers.. pretty simple but a lot of work.
Sadly ANYONE has the same ability but most don't care or are too lazy. So say what you want about my experience in this game, but I would be willing to bet a good sum that any non pvp rotation in ff14 couldn't possibly be more complex than most of the macros I have set up for some of my other games.
