I wasn't knocking your recommendation, but I think a lot of the people who are looking for advice here are assuming that slowing down the sewing machine to a crawl will automatically make them great sewers, and the only thing that will do that, at any speed with any kind of equipment, is experience. You can be a lousy sewer or a great sewer at slow speed as well as high speed.
Industrial machines are meant to be used at high speed and are usually run two or three shifts a day. They take some getting used to. Cutting the speed down to 50% of the machine's capability to start with should be plenty for the casual user. Learning how to use the treadle is very important, and if you try to slow the machine down so that the treadle is almost insignificant you can't learn how to operate the machine correctly.
Finally, nobody is suggesting that anyone should sew at full speed, I rarely do. My point is that knowing how to operate the machine correctly will make you a better sewer which will translate into better results.
No one lives forever, the trick is creating something that will.