[asherkin]

> The problem with freezing cards is that transfers are not direct: freezing the card on the banks end might work, but some ATMs or other systems might have a sufficient delay to allow (some) abuse while the card was 'frozen' by the user. The question will be who will pay for the delay.

This is part of why their cards are online-only, every* transaction has to be verified with them before it can complete at the reader - so transactions are slower, but there is no grace period after the freeze.

* as I understand it, certain merchants are white-listed on-card for offline transactions - namely TfL.