This is incredible, thanks for sharing. I had the exact same thoughts the author is describing in the beginning - how hard can it be? It turns out super hard. And one shouldn't forget that it is one of the few input methods to our computers. With voice not working properly and drawing on the mouse pad / touchscreen being too slow I would argue it is still the number one input method. So the expectations towards UX are extremely high and there should be no faults. I admire anybody who works on some kind of text input mechanisms from this day on.