CCC2 Speed Confusion

Okay, so I’m (finally) aware that the default speed for ST is the fastest speed (Turbo 3 US, Turbo 4 JP). Okay…now here’s something I found weird…On the Training Mode in ST, there’s five speed options: Slowest, 1, 2, 3, and Fastest. Is there a difference between “Slowest” and “Turbo 1”? Is there a difference between “Fastest” and “Turbo 3”? Do the numbers “1, 2, and 3” correspond to the Turbo setting numbers? If so, does that mean “Slowest” is Turbo 0 and “Fastest” is even faster than “Turbo 3”, which is supposed to be the fastest setting in the arcade version? Help would be appreciated.

yeah, I have wondered the same thing, whats the difference between turbo 3 and “fastest” in training mode?, but whatever guess its not a huge deal