As a high school student, I can confirm you explained it well and I was able to follow it the entire way though. :)

I think I discovered a tiny problem in your 'relative proportions' formula picture. you have

    y'   y
    -  = -
    z'   z'

in the first line. The z' on the bottom right should be just a z, right? Other than that, this is perfectly clear, and I understood it even though I just came out of high school and haven't started college yet! Absolutely fantastic work!

EDIT: Fraction format

Oops. Actually it's not a z' in the denominator in the second fraction, but a comma following the fraction bar. That's confusing; I have removed it. Thanks!

Congratulations. In my opinion, math is not easy to explain, but you did it very well. :)

Do you have any / know of any good documents about C obfuscation? I think that is the part that fascinates me most.

I don't know of any, but browsing through the archives of ioccc.org is probably an education in itself. That's where I got my own inspiration.