[seanmcdirmid]

I never said anything about why. Even if you are just instructing, do you care to see a wordless video or read an instruction manual? Actually it's not even that...which one is easier to write? The descriptive power of language is great when issuing imperatives; it must have been very hard to organize before language was developed 50-100 kya.

You can still communicate spatial concepts better with pictures, and maybe a hybrid approach might work, structured edited languages are very popular as vpls, but think about code with interspersed diagrams.