I think, apple should have also provide a feature for emergencies. Most of the people spend a lot of time in driving. In that case, say you have a responsibility to take care of your grand mother or parents or persons with special needs. You are the only help they can get and you have this iphone that blocks all the calls or texts that reaches you. Well i am not saying it is alright to get calls or texts while driving, even i am strict in using the mobile while driving. when ever i get a call or text from any important person, i just stop the car and respond. May be they should have a do not block option for certain contacts.