0.2 will certainly do a lot better than 0.1 with massive files, but probably not that well.
As for discontinuing it, it was more of a case of preferring to divert my time and effort elsewhere. Believe it or not, finding interesting ways to edit text files isn’t all that exciting. That said, if I ever need to be able to manipulate text in a manner not available in other tools, I will add it to Notepad.NET and share it anyway.