As someone who has written a considerable amount of Forth as a hobbyist, studied APL, and been paid to write K, it's fascinating to me how aesthetically similar the Forth and APL communities are, despite their languages approaching minimalism from completely different sides of the spectrum. I definitely credit learning to read Forth as helping to open my mind to the unconventionality of APLs. Spend enough time out there on the edge and you don't get as hung up on whether syntax resembles C or is "unreadable".
It's subtle, but I think making function declarations "lightweight" in this manner is important for encouraging factoring. In APLs the scale of the semantic units you give names to is a little different, but that's its own separate discussion.
It would be interesting to have a forth where, if you try to pop from an empty stack, you get a function object that consumes the next things pushed onto the stack (i.e. functions are curried)
I'm nowhere near your level of comprehension in either language, but agree that spending some time outside of curly brace land gets you more comfortable with other languages.
