Maybe if you divide a video to 3 segments or 4 segment you don’t have to go so fast so people can actually can learn from you or maybe that was not your attention to begin with
i think similar types of speed controllers are used for e.g. outboard motors within smaller ships. maybe scooters have comparable parts - but they indeed don't need a reverse mode.
I am still awaiting the mill I have ordered arriving in the UK (long wait due to Covid-19) and in the meantime I have been watching RU-vid vids on adding an X axix power feed. There are absolutely loads of them but I rate this one as one of the very best. There was no need for speech as it was clear what was being done.
the 6-USD parts from e.g. ebay might be one piece of the calculation. having the machine park and spending the working hours (not to count the tools wear) is sort of priceless (in terms of they were given not price at all).