I'm sorry, but what you're talking about sounds like it doesn't qualify as "programming" as much as web design and code plumbing. Note that in large part I'm talking semantics, here, in that my definition (and I suspect Joel's as well) differs from the way you're using the word).
I understand that you're likely paid well to do it -- as are plumbers. And it's a respectable job. I'm not trying to knock what you're doing.
But by your own admission your own code less than ideal. And Joel is talking about what a good programmer would need to be able to do, and if you want to start someone off on the path to becoming a good programmer, it's not a bad suggestion.
If you just want someone who can copy and paste code off of Github and doesn't really understand it, well, then you don't want a "good programmer" -- and frankly anyone worth their paycheck in IT probably already knows how to do that.