I have never really done it. I'm allergic to phone poles and cars. They make my bones break and nose bleed.
If my alerts keep going off, I'll pull over and have a look just in case it's an emergency with my daughter and it's her mom or the preschool trying to get a hold of me. Usually I'm frustrated because it ends up being one of my knuckleheaded golf buddies sending me links from theCHIVE or Buzzfeed.
Though, I've always had an iPhone 4... which did not have Siri. My new iPhone 5s is currently on the way, and I am told Siri will read your texts to you and you can talk a reply to her. So I'm gonna give that a whirl and see how it works out. Otherwise, it'll be how I've always done it.