This doesn't solve the issue of somebody traveling and getting mugged. Then what? You're just locked out of everything? That seems very, very inconvenient. The

This doesn't solve the issue of somebody traveling and getting mugged. Then what? You're just locked out of everything? That seems very, very inconvenient. There's a reason passwords haven't been usurped yet. It's because these fancy new ideas come with an entire new set of their own problems. These problems are worse than what we deal with for passwords.