cruise control is just a speed regulator it's a million times less complicated than a thing that keeps you in a lane and stops when things cross your path, i can write algorithms for this kind of power control, bitcoin has one and i made a more fancy one, and then a couple years ago someone pointed out that they are like a Proportional Integral Derivative controller used in physics experiments for various kinds of force and power regulation. 

 I guess I’m speaking more about the “efficiency” aspect when it comes to people driving their cars. Too many go into high rpm’s and back down again which wear out the engine sooner. That’s all