This is a follow on question from this answer by Spehro Pefhany, in which he explains to us how to use 74HC595 serial shift registers with only one digital output pin. Below's the picture he posted.
Out of curiosity, and also to evaluate whether I would be able to control a shift register myself, my questions are:
1. How complicated is it to control shift registers in this way with a MCU, in C, for example?
2. How would the firmware that controls this shift register look like?
3. Are there Arduino libraries to help us handle that (or for other platforms as well)?
I have no idea on how to start.