User Registration Match Behavior is Wrong - Should Create Link if Match Found

Currently, if a newly registering user matches an existing contact record - an error is thrown (record already exists). This is incorrect behavior. What should happen is that a uf_match (link) is created between the new user record and the existing contact record.

Not sure if we've already resolved how any incoming data on registration (civ profile) should be handled (should it over-write existing field values for the contact, fill, or get ignored ?). Safest to ignore - but then we're losing self-entered info ?? This is a bigger issue - so do what makes sense/is easy for now.