User blog comment:Nayuta Ito/An attempt to well-define OCF as a number notation/@comment-32697988-20190425100551/@comment-35470197-20190428072514

Since an addition&Coughinality-based ECF behaves like Buchholz's OCF, I guess that it is actually not so easy to define NIECF up to Ω_ω in the prvious approach, because the original UNOCF up to Ω_ω behaves differently from Buchholz's OCF.