This is droll but I think it inadvertently makes a good point: we should be using more aids like syntax highlighting for natural language. Natural language is

This is droll but I think it inadvertently makes a good point: we should be using more aids like syntax highlighting for natural language. Natural language is at least as hard to understand as artificial programming languages, and humans have (reluctantly) regularly improved the syntax highlighting of natural languages, by adding consonants, spaces, scores of punctuation marks, cases, and variant typefaces. (Consider trying to read something like ancient Hebrew in the original, written without spaces, consonants, punctuation, or lower vs uppercase - never mind italics or bolds!) Why don't we add more? Surely we did not invent the ultimate way of writing English around 1500 AD? The primary distinction seems to be that computer languages are regular enough to be machine-annotated. If you had to hand-typeset every line of code, syntax highlighting would be used only in the rarest of CS publications. (Sort of like color-coding in equations: incredibly useful pedagogically, but also so difficult to do in HTML or TeX on top of actually writing the equations that only the occasional enthusiast or particularly-determined teacher will bother.) Natural language is such a major challenge to annotate simply by part-of-speech that you need to be a linguist to do so reliably. So naturally, no one ever does, and anyone who might want to is deterred by the fact that no one else does so readers won't understand or like it. (Beginning programmers are often confused or distracted by syntax highlighting as well.) However, when you look at the best grammar/style checkers, or deep learning results on parsing natural language, it seems plausible that they've gotten good enough that something useful could be done with them...