Great comment! Yes, there are many other approaches that are more true to reality, to the point where they are fairly thorough simulations of physics. My approach is somewhat like a five minute figure drawing sketch compared to the equivalent of hyper-realistic 100 hour paintings. Neither is necessarily a better approach, but both are good for different goals. What I like about my approach is that it is very easy for me to understand and manipulate. I can take advantage of this to make new effects that are less like reality but still intriguing in their own way.

Author here. Thank you! Yes, I think you have the basic gist of it. Split each line, then move an endpoint. There's nothing too complicated about the algorithm, the trick is really around fine tuning all of the possible parameters. If it's not obvious, my approach is purely going after aesthetic effects.