If it makes you feel any better, I will often spend days or weeks writing such things that include a great deal of math and then look at it again after a day off and have no clue how it works.
With a lot of physics-based math the best way to see what everything does (assuming you don't understand the core concepts out of the gate) is to just tweak all of the vars that contribute to size, shape and movement to see how they work.
It's good to hear that even people familiar with this can easily get confused about it. I think it's a sign perhaps you should comment your code more :P
Seriously though it's the writing part that I couldn't do - I'd be happy to come back and not understand something if I could even write it in the first place!
With a lot of physics-based math the best way to see what everything does (assuming you don't understand the core concepts out of the gate) is to just tweak all of the vars that contribute to size, shape and movement to see how they work.