User blog comment:B214/Volume 22 spoilers/@comment-27083298-20161112215056/@comment-26821288-20161114203220

Well, Issei already has DxD, so he won't be needing IMT CCP anymore. And I think that maybe if Issei would master DxD, he would also natrually master CCP, because CCP is weaker. Although I only think so.