User blog comment:B214/High School DxD DX.4 discussion/@comment-30329599-20170630194447/@comment-10330822-20170714053110

Danger here is that I don't think we've seen 100% of what Issei can do yet. Which means its doubtful Saji can really be "prepared". Especially since we know Issei can use DxD G now, not just DxD, and he hasn't used that yet, meaning that Sona and Saji probably don't know about it. They probably also don't know that Roygun is advising/possibly playing for them either.