1. I am not a car engineer,or anywhere near it, but everything I've ever read about modern cars indicates their infotainment system and engine control unit are at very least on same bus and can and do communicate.
2. I don't have those numbers, in fact point of my post I'd that I don't know how we get those numbers. When I'm a passenger I'm terrified how distracted people can be by poor UI. I wish we had more hard data. Some studies are slowly emerging.
I'm all for forbidding touch screens for driver interaction in vehicles and I'm honestly surprised that this hasn't happened yet. Anything that takes your eyes of the road is a risk. Where I live we're pretty hard on smartphones in the car while driving (and rightly so) and yet we accept touch screens with menus four levels deep for basic stuff.
2. I don't have those numbers, in fact point of my post I'd that I don't know how we get those numbers. When I'm a passenger I'm terrified how distracted people can be by poor UI. I wish we had more hard data. Some studies are slowly emerging.