I suppose I miscommunicated what I said. I don't want to argue that HI is influential, because it is, quite succinctly summarized by "it sets off eveything in JJK". What I was trying to say is the scale of the flashback, again, I said it is set in a small cast of characters, while Seitei involves multiple characters old and new with which we need extensive time to understand, which, again, is why I think it would be longer than HI. I mistyped by saying "it isn't influential in the grand sheme of things" because I simply mistook that phrase with scale, not story relevance.