No, his code isn't ugly. No, not only he understands it. It is actually considered exceptionally beautiful (http://kotaku.com/5975610/the-exceptional-beauty-of-doom-3s-...).
Beyond that, even if it was (which it isn't), you are not John Carmack. I don't know if dropping him into the article was supposed to bolster your point, but I can assure you it did the opposite. It reads like an oddly malformed appeal to authority. Bonus point: you can look at his code: https://github.com/id-Software
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Please, please stop reading books about style and creating your own styles! Follow the language / platform standards and idioms so your code will instantly be readable by other developers. Almost all languages & platforms have dominant coding conventions, follow them. 15 years ago, you had to bake your own standard, you don't need to do it anymore.
Use your creativity on solving your problem, not formatting your code.