Event registration configuration - allows multiple registrations for same email address to be configured without requiring First+Last name for additional profile

We need to verify that either the PRE or POST additional participant profile contains First + Last Name fields when 'Allow multiple registrations from the same email address?' is checked. Currently we are only checking for profile of type Individual (or subtypes). If additional profile contains email only, registering w/ same email in primary and additional results in lots of notices.