From what I understand, this device was copied/plagerized from the Datel hardware/software copier. If I'm wrong on this please lemme know
As for the long tracks, I think there was a control line that connected to the spindle motor or the line that controls the spindle motor in the external drive. It pulsed rapidly and/or more slowly to get the motor to act like it was being turned off and on thus causing the motor to slow down and of course this meant you could write more data to a track! I think this was really a haphazard attempt instead of actually making a modified speed controller to do this, which is much more reliable as you can get the speed pretty darn close to what you need it to be