Mayuri has tricked Yamamoto. He is trying to get him killed. He is in league with the Quincy, and might be the reason they are still around. Why did he kill those people in Rukongai (or however you spell it) without asking permission first, even though he would have gotten it? Because he was playing the Old Man like a fiddle. He wanted Yama to feel impotent, to think that his subordinates were doing what needed to be done before he did, and to remind him of his failures ("you should have killed that man one thousand years ago"). Probably why his VC was murdered as well. And he was probably the man who created their anti-Bankai devices. Everythng that has transpired was orchestrated to get Yamamoto to fight Juhan Bach, and to die doing so. Mayuri's little talk was designed to twist the knife just enough so that, when his subordinates started losing their fights, Yama would snap and go straight into a suicide battle- cause lets face it, Yama is not going to win; no tension in that. Might as well put it out there that I still think Mayuri was one of the two people with Aizen in Turn Back the Pendulum turning people into Hollows (because Gin was too short to be one of them), and following this that his experiments on the Qunicy might have been motivated by more than just curiosity, and had more of a purpose, maybe to create more Quincy which is where all these new ones come from. All of this is a long winded way of saying I want my jerk back. I want the evil bastard Mayuri Kurotschi who beats his daughter for no reason and sends his subordinates on suicide missions, who forces fathers to set their sons on fire and is just generally not a nice person. Thats the Mayuri I hope we see sometime soon.