We had swipe cards at university which did this sort of tracking and this was in the early 90s. It was not uncommon to take 3-4 people's with you to swipe and

We had swipe cards at university which did this sort of tracking and this was in the early 90s. It was not uncommon to take 3-4 people's with you to swipe and register. When they worked this out, it was scrapped instantly. Stuff like this doesn't work, unless you're selling it...