Why would you go from a single step of resting your finger on the Touch ID to two steps of Touch ID and then pressing the home button to unlock the phone? The only reason I can think of doing away with slide to unlock now is the removal of the home button and bottom bezel with the shifting of the Touch ID to the back of the phone next year. The Touch ID will be just a non button sensor at the back of the phone and one will have to press anywhere of the display in front (think Magic Trackpad) and then touch the fingerprint scanner behind to unlock the phone. Else why fix what was not broken.