For your website, security is unimportant, so the user can just use the password "password" that they use for all other sites where the password isn't important

For your website, security is unimportant, so the user can just use the password "password" that they use for all other sites where the password isn't important. Logging into every site as brian@briansmith.org/<generic password> is noticably more convenient than logging in with OpenID. Logging in with a username and password is faster than logging in with an OpenID, because the OpenID protocol requires several HTTP requests per authentication, whereas a usernmae/password only requires one.