At least this one actually seems to remember their inputs well enough, I wonder how many times they practiced? I've seen similar videos before and it is hilarious to watch when they're trying to recall the chords they programmed.
I don't see this scaling for real projects with thousands and thousands of complicated identifiers, camelcase, crazy abbreviatin, acronyms, etc. Each project is going to have its own set of identifiers and you're going to need a custom dictionary for each of them.
Steno is great for natural languages that evolve very slowly over time and which can be largely learnt once and then used forever. Code is a rather different beast.
I know. It also takes only a few seconds to look up a word in a dictionary.
It takes much longer to memorize thousands of ever-changing chords for different projects. And when you haven't memorized them, typing is going to be very slow and awkward. Kinda like trying to write an essay when you need a dictionary for every other word.
I'm skeptical of this. A chord sequence is of similar complexity to an identifier (the keys on a stenotype keyboard have mnemonic designations to make this easier), and people memorize commonly-used identifiers just fine, as part of getting familiar with a new project.