I think this is a great article about something that I didn't understand. However, as feedback, what separates this from top tier articles is a lack of pictures and diagrams. Just adding a few of those to illustrate the different types of walls would make this content more engaging and link it to real world examples. I'm not likely to google "soil nail", but I'm def open to spending more time on your page to check out an example.
Grady's web site seems to be experiencing the HN hug of death right now, but I watched the video last night on Nebula, and there definitely are visuals and they definitely clarify the lecture. And as usual, Grady has built a practical demonstration of the forces and it also helps.
I thought the article was in a weird place. It read like a very long introduction. If its the first in a series, its great. If its a standalone article, it lacks needed depth.
