User blog comment:B214/General Discussion/@comment-27180505-20170331135923/@comment-96.246.181.213-20170331233248

whether or not it matters for issei is irrelevant because as far as we know, nothing has confirmed how his ex form works. nor do we know how big draig could make issei without GR's flesh. what's important here is that there is more to dragonification then simply the flesh, as we have quotes on the subject that indicate that it has to do with either dragons aura or dragons blood as well. perhaps having actual flesh makes it easier, but i dont think it is a strict requirement.

this is less important for issei and more for anyone who could may need a power up down the line with a containment type sacred gear.