It's perhaps only tolerable in situations where a site has to deal with phishing on a large scale basis, perhaps on a forum targeted towards a younger audience.

It's perhaps only tolerable in situations where a site has to deal with phishing on a large scale basis, perhaps on a forum targeted towards a younger audience. And even then, only if it is only a banner which says "WARNING: Don't give out your password to sites you clicked on from us!" as well as a swift way to see the page in full.