This won't keep a Glass from recording. The default recorder lights up an LED when recording. If someone goes to the trouble of getting an app that doesn't light up the LED, why wouldn't they use a better recording device, like the phone they already have? Assuming that Glass users are recording or streaming everything never made sense to me. Also it would kill the battery in about 3 hours.
I like the idea but using a "...unique character string that he says he’s found in the MAC addresses of Google’s augmented reality headsets" seems problematic.
I thought MAC addresses consist of three bytes vendor ID and three bytes serial number so I'm not sure how you could filter other than on a range of serial number for a specific vendor. That might boot off devices other than Glass.
> it was not possible to know whether they were recording
That's false. If you spend 2 minutes learning about Glass in person, you can tell if it's recording or not. (If it hasn't been rooted and modified.)
Furthermore, if someone WANTED to record you without your knowledge, the LAST device they would chose to do it with would be Google Glass. It'd be like walking around with one of these:
