As you respond to that text from your friend, you look intermittently at the road, then back down at your phone. No worries. You're a good driver and a great multi-tasker. You've done it plenty of times before. What can go wrong?
It only takes a short break in concentration for the unthinkable to happen. Fact of the matter is, if you're not paying 100 percent attention to the road, you are gambling with your life and the lives of others.