On: TfL's simple pop-up message led to a significant d...

[eesmith]

To hinder traffic analysis across multiple trips, you should also have meeting where you swap Oystercards with others, similar to how people would (and still do?) swap grocery purchase tracker cards with each other, to get the discount with less surveillance.

[fullspectrumdev → eesmith]

I used to do this with a few people.

The system breaks down when one guy stops topping up their card knowing they can be a prick about it :)