In J, I think it's very difficult to move on from the initial stage of dealing with "line noise" as the author mentions.

For me, this was further complicated by the fact that error messages are very hard to understand in the beginning.

I've written an article that describes how I typically deal with solving most of the domain/rank/length errors: https://www.justus.pw/posts/2020-07-31-errors-in-j.html