Unexpected "select CO" for org identity with multiple co people in same co

If a given org_identity_id has multiple co_person_ids within the same CO, when the org_identity_id logs in it will be presented with the "select a CO" menu with only one CO to chose from. This is because Co->find in cos_controller:select() returns multiple rows (one per co_person_id) which in turn generates multiple CO rows.

Under most circumstances, a given org_identity_id should have only one co_person_id per CO, so it may not be worth fixing this.