Is he distracted?

Focused?

Impatient?

Does he have road rage?

Overtake people?

Speed?

Stop for police/ambulances?

I this is probably the best test for a getting real glimpse into someone's character. Anyone can put on a show interacting with waiters, but driving is an ingrained habit. It's hard to fake it.

My lv dad is one of the most impatient people I know. Two days ago he ran a red light with both me and my mom in the car. He doesn't care enough to drive safely for us. This shows in other aspects of his life too