Purely cadence based PAS is useless. With a powerful drive like even my small block, basically every time you start to pedal at all the drive takes off and leaves you clown pedaling. If the point of PAS is to get some exercise while extending battery range, pure PAS with no other controls accomplishes nothing except maybe on the puniest of 250w mid drives that barely make human power.
Where PAS really starts to work is when you add other parameter controls to it. Grin Tech has digital two button switches that allow as many as 20 presets of power and speed. You can absolutely fine tune how fast you go under PAS and how much effort you expend at that speed. Just in case 20 levels of power isn't enough adjustability, you can also connect an analogue potentiometer or 3 position switch to control other parameters at the same time. Here are some of the auxiliary parameter controls available: http://www.ebikes.ca/shop/electric-bicy ... input.html
As far as feeling like Superman, there is a long, steep winding back road that leads to my house. Bicyclists love it because it's scenic and the traffic speeds are lower than the main streets. You constantly see cyclists standing up in first gear pumping away up this road. I can do 35 mph up that road which is faster than most of the auto traffic due to the tight turns. I use the two button switch to adjust the amount of assist that I get from the motor to get exactly the workout that I want. When I can choose exactly how fast I go, and how much exercise I get while maintaining that speed, that's all I want from pedal assist. If I want something outside of all of those other controls there is always the hand throttle.
Here is a video wherein Justin outlines the functions of the new parameters switches with the CA3 v3.1: