Take a look at the code. He makes use of both Gotos and global variables.

See paragraphs 5 & 7.

He would have been rejected as a job applicant immediately as soon as the paragraphs were read.

We have brainwashed ourselves with dogmatic theory. I see nothing wrong with the code. This code is not for business production. It works well for what it is. Un-brainwash yourself! It's great that Knuth doesn't have to apply for a job and go through the gauntlet because that would make Knuth un-Knuth!