But workers at high security facilities don’t mind invasiveness. They happily put up with slow acquisition and processing times for iris scanners because they know that accuracy is paramount. A False Accept is disastrous in these places, and in order to keep the False Accept Rate (FAR) down (to say 1 in a million) they trade off an elevated False Reject Rate (FRR). That is, workers out up with the inconvenience of the occasional retry, in the name of security.

So the fancy new shoe doesn’t solve any urgent problem. Moreover, even if it did, the security managers looking after missile silos aren’t going to jump at the next biogimmicks, fresh out of the R&D lab or sports store. Security is a conservative game, and high security is highly conservative. No serious solution to a serious problem is adopted until it’s been peer reviewed, standardised and field tested over years and years.

Here’s a test: ask (as would a DoD security manager) for the Detection Error Tradeoff (DET) curve for the biometric shoes? This is the most basic characteristic of biometric system yet few vendors will talk about it publicly, and not enough commentators appreciate how important it is for evaluating these technolgies.

Without a DET curve, biometrics are still science fiction. Literally.