Yea I know about the saving of time arguement, but just how long does it take to unlock your phone? 1 second? 2 seconds?
If she is owt like my wife, it will take her 5 minutes to find it in her handbag. Besides, if you're being raped, I doubt you have time to press 4 buttons, ask for the Police and explain the nature of the crime and your whereabouts. Plod will no doubt stroll along half an hour later, when he's finished lecturing motorists and smokers to take a few photos of your body. If (heaven forfend) you are ever in that situation Wenchy, I advise you to scream your lungs off and run like fuck.