Great tutorial. About 20 years ago, I was a Level 4 user (by the article's definition), but that knowledge faded with disuse. When I switched back to a Linux/UN

Great tutorial. About 20 years ago, I was a Level 4 user (by the article's definition), but that knowledge faded with disuse. When I switched back to a Linux/UNIX machine about a decade ago, I started using vim again (well, I started using vi again, but it was vim), and remembered a lot of Level 1 and 2 stuff, and could recall being able to do more, but never had the motivation to crawl through the man page to force myself to recall how I did more. This article is so logically laid out I think anyone could get to at least Level 3 with the article and a few hours diligent practice. Level 4 would then beckon.... When I became a serious sed - and then ed - user, I became a much better (faster, more productive) vi/vim user when I didn't need to be in visual mode all the time.