One tree doesn't make a forest, from whatever implementation that was taken out of, and naturally there are always magician tricks that PyPy also uses.
*iirc* pretty much all of the Smalltalks (that was CUIS).
~
"Creating blocks in Smalltalk has always been a potential source of performance problems. … In Resilient, we have restricted blocks to be last
in-first-out (LIFO)…"
https://blog.bracha.org/resilient-paper.pdf
"Digitalk’s Team/V unobtrusively introduced a non-reflective syntax…"https://wirfs-brock.com/allen/posts/914