I'm the original author of that thread by the way.
It's 100% completely within the TOS/EULA. The script is there for you to see, nothing is hidden and anyone who can read it will tell you that it's not automating anything.
It remains 1 manual user input = 1 keypress output which is what Blizzard allows.
If you leave your computer, or take your hands off the mouse and keyboard, the keypresses
immediately stop sending to World of Warcraft. Provide use input again and the keypresses will resume. In otherwords, take away the manual human input and the script will stop working, because if it didn't then that would be automation.
You can also take a look at the
Consortium Key Sender which is a more polished program that does the same thing. Sends a keypress to World of Warcraft whenever you perform a user input via your keyboard or mouse.
You are welcome to make an account on The Consortium Forums and ask for yourself, the majority of the community there uses it and no one has been banned because it is allowed and within the rules.