User blog comment:Piyush Banerjee/Shin DxD 2 discussion/@comment-2.247.243.13-20181220200346/@comment-33939194-20181221065740

Ajuka said it wasn't that Issei was too weak but that it's because Ophis power was split between her and Lilith and if they resonate, then Issei will be able to unleash the full potential of the 8 mutation pawn pieces and allow to use True DxD without problems.