Code review comment for lp:~jamestait/canonical-identity-provider/lp1648775-email-reminder-of-paper-exhaustion

+1, FWIW most users *should* have a preferred email, but I think it's good to just warn instead of blowing up if someone doesn't. If we care about users having a preferred email, we could enforce that some other way. But "that is another story and shall be told another time".