User blog comment:B214/Volume 22 spoilers/@comment-27083298-20161112215056/@comment-10330822-20161114170952

Maybe not, chances are Issei is even stronger than he was when he fought against Apophis. I mean, he defeats Baraqiel and the rest of Team Lightning with DxD, but he is seen just talking to Ajuka and the others afterwards like nothing happened. Implying his control over DxD has grown. If that's the case, he might already be stronger than Crom.