I think the author of the blog post understands JS scope rules. His point isn't that you shouldn't need to have a "var" in front of your declarations or that javascript is stupid and he doesn't understand it, it's that there should be a better way to find bugs like the one that bit him.

Of course, there is a way to find his particular bug (JSLint, "use strict") that he didn't know about. Still, the point about debugging being a nightmare is absolutely true.