User blog comment:Silver-Haired Seireitou/Sake Time with Sei - Can Arrancar Use Kidō?/@comment-30807545-20140413170104/@comment-30807545-20140413171809

You're forgetting Epzi, Aizen was the one who created the Hollowification Virus that led to Shinigami getting Hollow powers. Then, using that amount of data and combining it with the data and hogyoku he stole from Kisuke, he was able to achieve the necessary steps to break the boundary between the two races - thus born the hogyoku in which he wielded. Astsatted before, Hogyoku's main power is desire materialization. If the arrancar wished to, by using the orb's power, they can gain the ability to use Kido, just as how visoreds can use hollow powers. So yes, the orb plays a very big part in all of this.

Also, in the manga, as you know, there's a lot of asspulls that can't be explained thoroughly X3