The only thing that's worse is that they might feel secure when they're not.
That is exactly what an ISP would want. You would have the correct URL, the correct IP address and everything would look correct. But your traffic would be monitored by the ISP (in some kind of transparent proxy).
Being able to save a certificate and not having a message pop up every time it is seen would be useful. The first time you came across a certificate you should get a warning message. But if you can manually verify the certificate then you should be able to silently accept it in the future.
Ya'll hear about the geometer who went to the beach to catch some rays and became a tangent ?