IIRC, Ford has a simulator just for testing these controls in the cockpit. They design and implement a cockpit, mount it to the simulator and run some scenarios like animals crossing roads or someone braking hard in front of you.

I drive a 2001 focus, and all controls can be operated so-called blindly. I can do anything (HVAC, hazards, lights, etc.) without moving my eyes from the road. I think it's very important.