APL programmers would say it's already maximally optimized for readability (actually, it could be improved further with less and shorter keywords and stdlib fun

APL programmers would say it's already maximally optimized for readability (actually, it could be improved further with less and shorter keywords and stdlib function names). That's not even a joke or dig at APL programmers, whether that code would be more or less readable with longer, more descriptive names is entirely a matter of perspective, preference, and context.