Without question, all intelligent people shared a common flaw: they liked seeing others being toyed with in the palm of their hand.
Aizen was an especially outstanding example.
After successfully using Momo Hinamori to mislead Toshiro Hitsugaya, he quickly began putting on an acting performance with Gin Ichimaru.
The two clashed repeatedly in public, behaving like sworn enemies.
Aside from a very small number of people in the know, no one would have believed those two were actually on the same side.
Poor Shiro had fallen completely into the trap. He had begun to suspect Gin Ichimaru as well, utterly unaware that he had already been played.
Of course, none of that had anything to do with Allen.
The role he played was merely that of a 3rd Seat, so he was not qualified to attend the emergency meeting convened by the Captain-Commander. He only slipped out in secret to meet Sakura when he had the chance, then patiently remained in the 5th Division the rest of the time, waiting for his part to arrive.
In his view, this so-called Ryouka invasion was entirely an intellectual contest between Kisuke Urahara and Aizen.
The former clearly knew that the latter was after the Hogyoku, yet he had not removed it from Rukia Kuchiki's body in advance. Instead, he had set a trap, intending to expose Aizen's disguise and rebuild an Alliance with the Soul Society to deal with the mastermind stirring up trouble from the shadows.
The latter had simply gone along with the plan. He had no intention of staying behind at all, instead arranging a grand farewell ceremony for himself before taking the Hogyoku to Hueco Mundo to establish his own Arrancar army.
It could be said that both of them were carrying out their own carefully laid plans,