Okay, I still don't think you understand the point of Dragon Dance.
Dragon Dance is an attack to be used by Physical Sweepers. The whole point of having Flamethrower / Fire Blast on Charizard is so that it can wipe out The Common Physical Tanks, which it really doesn't need any Special Attack EVs in order to accomplish.
The -Atk nature matters a MEGALOAD, no matter how it's used. It makes Dragon Dance completely useless, as Charizard still does **** to anything that comes its way (Let's face it, 180 Atk x1.5 is only putting Charizard at 270 Atk, and that's not even enough to consider him even a minor threat :p). Charizard with a +Atk Nature, and 1 Dragon Dance puts him at a lethal 434, which is WAY more than a meager 270.
What you're trying to do is useless, which is run a Physical Sweeping Set with a -Atk nature and max SAtk. There's no point of using Dragon Dance AT ALL if it's not being backed by a +Atk Nature. And there's also no use of all of those SAtk EVs and you're only using one special attack.
In short, Charizard with Dragon Dance needs to be ran with a +Atk Nature, and does not require SAtk EVs when you're only using One Special Attack, which purpose is to KO Skarmory, Steelix, Forretress, and Scizor.
You may take this for whichever kind of explanation that you please, but I'm just about tired of trying to explain it.