Well done. This is one of those things I'd never thought of, but is obviously correct now that you point it out.

Comments on how to expand / rewrite this post would be appreciated, as I feel like I could move it to Main with a little work.

I don't think this needs expansion. Brevity is a virtue, and this does a good job of explaining the core idea quickly and accessibly. If you run it through a spellcheck and spend fifteen minutes making the prose flow more smoothly, I'd consider it ready for Main.