You seem to have a real hang up on the term "mad". The show has obviously laid the groundwork that there are concerns about Dany amongst her advisors and if she goes all out on Kings Landing she will kill a bunch of innocents and this would be a bad thing. So how do you think that's going to play out? Is it all a red herring and she's not going to do it? Is she going to do it and no one's going to care? Is she going to lay waste to kings landing and it will end up being her downfall? Personally I think it's the last. She wanted to publicly offer Cersei peace so the innocent would no who to blame when she killed them (a pretty distressing thing to say, by the way). Whether you want to call that the action of a "mad" person or not, it will certainly be perceived that way.