Between when you select the skill and then it happening, which I am talking about when an Action Sequence, gets to like a point where it's around 100 lines or more, you start seeing like 1,2,3 seconds of delay past that kind of point. Even if the skill isn't dual wield, but you plugin is active it will cause this, when yours is off it has no delay even at that amount of lines, you could probably see for yourself if you copy and past just a normal attack sequence, a bunch in an action sequence and can find out if you have it also.
it isn't exactly something that causes it to become usable, just need to try more optimize them better if they are one that gets to be so long, just thought id see what you think, since base Action Sequence doesn't seem to have this happen to it.