[tomsmeding]

I think that here you've made a great point. For many users, the level of privacy that Whatsapp gives is unnecessary, but if you are the person that needs to discuss mission-critical matters over Whatsapp, they give you the possibility to do that safely.

The only problem would then be that they can MITM one message, even if they'd be caught that way. I doubt they'd do that for less than world-changing messages, but still that's the only problem if you enabled the notifications and checked the numbers.