Earlier quoted context omitted.
This reminds me of a book called "numerical recipes in C", full of algorithms that were very useful except you couldn't really use them because the authors protected their use with a very restrictive license.
Did you know that you can't use copyright to protect an algorithm?
(It's similar to the early days of heat engines, where a guy called James Pickard managed to patent the crank, preventing other engine manufacturers from using cranks and forcing them to use a sun-and-planet gear arrangement instead: https://en.wikipedia.org/wiki/Sun_and_planet_gear )