I was nodding my head in agreement for most of Ben Brooks' article "On Hacking", with a few minor differences: I have taken courses on the subject, and I work mostly on Squarespace as opposed to Wordpress. Still, he says something that completely mirrors my own experience:
The entire theme for this website is one big hack. Nothing more. That’s why it loads a bit slower than “good” themes, but it is my hack and I love it.
I couldn't have said it better myself. Furthermore:
Hacking away at stuff I don’t understand is how I got the skills and knowledge I have today.
There's absolutely nothing wrong with self-teaching, experimentation, and "tinkering" as the basis for one's skills and knowledge. Dare I say, much in the way of formal education is for the most part entirely overrated; one is plenty capable of becoming competent (or masterful) by trial-and-error alone. As a matter of fact, I tend to prefer this approach.