User blog comment:Zwann/Vasto Lordes in the Espada, let's analyze./@comment-1432572-20091017013512

Rejuvination, you should remember that Yammy didn't even attempt to use his released form in the real world. He only did so in Hueco Mundo, where the reishi is far more abundant. He was also considerably much larger in Hueco Mundo than he was in the Real World, which leads me to believe his Resurreccion can only happen in Hueco Mundo. Think about it.