https://news.ycombinator.com/item?id=15095626

Probably did not wait long enough for the reply button to appear.

Though I'd check my ballast too, and probably read a book.

It's not even just that, it's worse at managing the use of the gas overall than a human with regards to cars as of 2015, it seems like the system is worse at managing the gas than humans are. I'm not a huge fan of cruise control as defined above because I find it makes me really inattentive (my problem, of course), but the benefit of not using the cruise control is that it seems like you get much better mileage. My family used to have to drive regularly between Minnesota, Wisconsin, and Illinois for a few years, and I would always get better mileage not using cruise control than my brothers (who used cruise control) would. The difference would often be as much as half a tank of gas or more on older cars (2000-2010) and on relatively newer cars (2015) it'd still be a difference of a fair number of gallons.

I think the systems just aren't good at predicting when to coast and when to accelerate, and for very hilly regions, this means a lot of wasted gas.

Another feature is speed warnings, which "beep" at you when you exceed them. Currently they only seem to be singular, but it should be possible to integrate them with satnav and speed sign recognition. I expect these would be safer, especially if it linked up with a, "black box" to report excessive violations with a parent, insurance company, police etc.