Earlier quoted context omitted.
I am not claiming to support that it is the worst. Just saying that, if it helps you type faster by keeping the device from jamming because you are typing too fast, then it is by definition helping you type faster by limiting the speed that you can type. Hence, slowing you down so that you don't go so fast that you crash. As per the claim of the fastest typist. I would be shocked it steno doesn't win that, hands down…
That's some tortuous logic. If it helps type faster by keeping the device from jamming, then... it helps type faster. If it only jammed because you type too fast, you could(/must) just slow down, no fancy layouts necessary. It didn't jam because you pressed any key too fast, it jammed when you pressed adjacent typebar too fast, and with proper layout (making sure that common digrams weren't on adjacent typebars) thes…
So... yeah, it is somewhat convoluted, but not as much as you seem to be implying. Take "kids chopsticks". They speed up kids, obviously. They slow down folks that know what they are going.
(Really, I could probably list a huge list of things that all work in this vein.)