Hopefully not. Because then all they have to do is beat you senseless, unlock your phone by pointing it at your unconscious face and deactivate the facial recognition feature to take it home.
Gee, and I thought the fingerprint sensor was easy to fool. Had I known Apple would give phone thieves a better feature just one generation later, I wouldn't have invested the effort to develop something.
Uhm, how is this worse than fingerprints? Before this `all you ha[d] to do' was beat you senseless, unlock your phone by using your unconscious finger, and deactivate.
For rather extreme values of 'all they have to do', of course, because this is kind of assault is quite prone to draw the attention of any passers-by.