Leaving the "working-memory-max=4" hypothesis aside (I'm sure it's all true), the "stack learning" paradigm has been hugely successful for me post-classroom, and (amusingly) specifically with Quantum Mechanics.
About ten years ago, I tried to understand what QM was about, by doing exactly what the article describes, starting at Wikipedia's "Quantum Mechanics" page. I got the exact result described: no understanding of the material.
However, the search eventually led me to ocw.mit.edu, where the same LIFO-based stack learning was super effective. Along the way, a refresher calculus course (also from OCW) got pushed onto then popped from the stack, as did the course "Vibrations and Waves" and the entire Walter Lewin lecture series (he has since been removed from OCW, but can be found on youtube).