That's me, too. I've read the essay many times, and I'm always scratching my head either at how the pieces fit into the big picture, or what various components

That's me, too. I've read the essay many times, and I'm always scratching my head either at how the pieces fit into the big picture, or what various components or jargon means. Like, what's a penstock? What is "head"? I can Google these things and eventually come to a pieced-together understanding, but it would be a lot more meaningful and educational if explained by one person.