I have experienced that users type in their credentials in the login box, even though SAML is configured and they are told to use the SAML login button…
this would remove alot of confusion and unnecessary support tasks.
Despite my poor UI design skills i still beleive the idea has merrit, from a usability perspective - it should be fixable by a conditional and some simple CSS.
and it would really be helpful! - we are experiencing much confusion about login (people tend to use the top option, even after getting told to use the other option)